Effort Testing in Dementia Assessment: A Systematic Review

Effort Testing in Dementia Assessment: A Systematic Review Abstract Objective Interpretation of neuropsychological test data is only valid when appropriate effort has been exerted. Research, however, suggests that neuropsychologists do not always formally test for effort and that this may especially be the case in the context of dementia assessment. This review systematically examined the literature that has investigated the use of both purpose-built and embedded effort-sensitive indices in dementia, mild cognitive impairment (MCI), and healthy control samples. The aim was to determine which tests of effort are most sensitive to suboptimal effort and least sensitive to the type of cognitive impairment seen in dementia. Methods A systematic search of databases was conducted to October 2017. There was no start date. Results Twenty-five studies were included for review. The studies were divided into two categories according to methodology. One category of studies (n = 5) was reviewed using a tailored methodological quality rating checklist whilst the remaining studies (n = 20) were reviewed using the Crowe Critical Appraisal Tool (CCAT). Conclusions The results of this review suggest that PVTs which take a hierarchical approach to effort testing such as the WMT, MSVT, and NV-MSVT are preferable for use with older adults who are under investigation for possible dementia. These tests go above and beyond the traditional pass/fail approach of more traditional tests of effort because they allow the examiner to analyze the examinee’s profile of scores. The methodological limitations and challenges involved in this field of research are discussed. Dementia, Mild cognitive impairment, Malingering/symptom validity testing, Elderly/Geriatrics/Aging Introduction Cognitive testing is used in many clinical settings, alongside information gathered from other sources, to develop a comprehensive understanding of a person’s difficulties. Scores on cognitive tests are usually interpreted alongside published normative data which assume that the examinee has put forth good effort. The value and accuracy of an assessment, therefore, relies on the quality of the data to be interpreted and, as such, it is of great importance that the clinician has evaluated the examinee’s level of effort and motivation during the assessment process. Effort testing is considered a crucial component of neuropsychological evaluation according to both the British Psychological Society (BPS; McMillan et al., 2009) and the American Academy of Clinical Neuropsychology (AACN; Heilbronner et al., 2009). This has led to the creation of both purpose-built tests designed to detect non-credible effort such as the Test of Memory Malingering (TOMM; Tombaugh, 1996), the Word Memory Test (WMT; Green, 2003), and the Rey 15-Item Test (RFIT; Rey, 1964) and those which have been developed from existing neuropsychological test batteries such as the Effort Index (EI; Silverberg, Wertheimer, & Fichtenberg, 2007) and the Effort Scale (ES; Novitski, Steele, Karantzoulis, & Randolph, 2012) both derived from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS; Randolph, Tierney, Mohr, & Chase, 1998). Effort tests are also known as symptom validity tests (SVTs) or performance validity tests (PVTs); however, Larrabee (2012) distinguishes between these two terms. SVTs are self-report measures which tell the examiner whether a person’s symptomatic complaint is reflective of their true experience of symptoms whereas PVTs are cognitive tests which allow the examiner to know whether the examinee’s test performance is reflective of true cognitive ability. For the purposes of this review, the term PVT will be used alongside test of effort. There also exist published criteria which can aid clinicians in making a judgment about an examinee’s level of effort or motivation. One such set of criteria was published by Slick, Sherman, and Iverson (1999) in a landmark paper which encouraged clinicians to apply a “discrepancy method” to their judgment of poor effort (e.g., attending to inconsistencies between test scores and observed behaviors from the same domain). Slick et al. (1999) propose inspecting an examinee’s pattern of performance (e.g., comparing scores on easy and difficult items to identify inconsistent patterns of scores) alongside evidence from other sources such as the presence or absence of a substantial, external incentive and significant inconsistencies or discrepancies in the individual’s self-report. Despite these recommendations, however, it appears that effort tests are not always routinely administered as part of cognitive assessment. One study which surveyed 130 UK neuropsychologists about their practices and beliefs regarding tests of effort found that while 59% of respondents working in forensic settings said that they always used a test of effort, only 15% of respondents working in other clinical settings said the same. One-third of the respondents in this study said that there was no need to use a dedicated test of effort because non-credible symptoms were evident from the results of other tests and from the client’s general presentation during assessment (McCarter, Walton, Brooks, & Powell, 2009). Research has found, however, that clinicians’ subjective evaluation of test validity is often highly inaccurate (Faust, 1995; Faust, Hart, & Guilmette, 1988; Heaton, Smith, Lehman, & Vogt, 1978) and that analyzing performance on traditional neuropsychological measures alone is an unreliable method of detecting invalid or malingered performance (van Gorp et al., 1999). It should be noted, however, that there is a cultural divide regarding the use of effort testing as research has shown that a majority of clinicians in the United States routinely test for effort as part of neuropsychological assessment (Schroeder, Martin, & Odland, 2016). It may be that some clinicians consider effort tests to only be of relevance when there is suspicion that an individual is deliberately feigning symptoms and indeed the majority of the literature on effort testing focuses on populations in which the deliberate feigning of symptoms is thought to be most prevalent, for example medico-legal settings and disability payment assessments. Nevertheless, literature does exist which examines the validity and reliability of effort testing in various clinical groups such as brain injury (Green, Rohling, Lees-Haley, & Allen, 2001; Hampson, Kemp, Coughlan, Moulin, & Bhakta, 2014), depression (Ashendorf, Constantinou, & McCaffrey, 2004), chronic fatigue syndrome (van der Werf, Prins, Jongen, van der Meer, & Bleijenberg, 2000) and conversion and somatoform disorders (Boone & Lu, 1999). There is, however, a lack of information on how people with varying degrees of mild cognitive impairment (MCI) or dementia would be expected to perform on tests of effort as individuals with dementia are often excluded from samples used for effort test validation (Dean, Victor, Boone, Philpott, & Hess, 2009). It may be that tests of effort are not routinely validated in samples of older adults who are under investigation for memory problems because it is thought that they are unlikely to be feigning symptoms. Indeed, a study found that as few as 2% of litigants and those seeking other forms of compensation alleged dementia (Mittenberg, Patton, Canyock, & Condit, 2002). It is important, however, to approach the issue of effort from a wider definition than that of deliberate malingering. There are many reasons unrelated to financial gain that can result in non-credible effort such as: depression, medication side effects, stress, lack of interest, fatigue, lack of comprehension of the utility of the tests, or motivation to be in a “sick role” (Barker, Horner, & Bachman, 2010). When conducting cognitive assessment with older people, it is also important to consider medical and physical issues which could effect on an examinee’s performance on a test of effort such as visual impairment/disturbance, language difficulties, and chronic health conditions which can cause fatigue. In order for clinicians to be able to adequately assess the reliability of data resulting from cognitive assessment in older adults presenting with memory problems, they must know which effort tests are the most suitable for use with this population. To date, there is no systematic review which examines the literature on the use of effort testing in dementia assessment. Systematic Review Objectives This review evaluates the literature on effort testing in dementia assessment with the following objectives: review which effort tests provide the lowest rate of false-positive error in people with MCI and dementia and to examine the relationship between dementia severity and false-positive rates. Methods Search Strategy The following electronic bibliographic databases were searched: PsycINFO, Cinahl, EMBASE, Medline and Psychology and Behavioral Sciences Collection. The search did not have a start date limit. The end date was October 2017. The following search criteria were used in all databases: ([malingering OR “test* of effort” OR “symptom validity test*” OR “symptom validity” OR “effort test*” OR “validity test*” OR “performance validity” OR “non-credible effort” OR “suspect effort”] AND [dementia OR MCI OR “mild cognitive impairment” OR “geriatric*”]). Titles and abstracts of studies identified were examined to identify those pertaining to effort testing in dementia assessment. Reference lists of all included papers were also examined to identify any further relevant studies. All the titles and abstracts of identified papers featuring the use of effort testing in dementia assessment were screened against the following criteria: Inclusion criteria Studies investigating the performance of dementia and/or MCI samples on tests of effort. Exclusion criteria Studies which solely used a sample of participants asked to simulate MCI or dementia. Single case studies. Methodological Quality In order to rate the methodological quality of the studies included in this review, the studies were separated into two different categories based on their methodology. The first category pertained to papers in which a reference standard is used to establish if a diagnosis is present or absent in the participants (in this case, the diagnosis would be credible or non-credible effort) and then results on the index test (the effort test(s) of interest) are compared between the two groups. A reference standard is the best available method for establishing the presence or absence of a particular diagnosis. To rate the papers included in this first category (n = 5), a checklist was developed based on the SIGN Methodology Checklist 5 for Studies of Diagnostic Accuracy (SIGN, 2007) and the Standards for the Reporting of Diagnostic accuracy studies statement (STARD; Bossuyt et al., 2015). The quality rating checklist had a maximum score of 28 points. The second category covers the majority of the papers included in this review (n = 20) in which the researchers have recruited a sample of participants whom they consider not to meet the diagnosis (of non-credible effort). In these studies, the researchers have either excluded participants who may have motivation to feign impairment (involvement in litigation/in receipt of disability payments) or they have assumed that their sample will exert credible effort by virtue of having a diagnosis of dementia/MCI. To rate the methodological quality of these papers, the Crowe Critical Appraisal Tool (CCAT; Crowe & Sheppard, 2011) was used. The CCAT contains 54 reporting items in 8 categories and has a maximum score of 40 points. All papers were rated by the author. A second rater assessed 12/25 (48%) of the papers to examine the inter-rater reliability of the checklists. Across all the checklist items in the quality rating tools, there was 84% agreement between raters. Where discrepancies occurred, these were resolved through discussion. Outcome of Search Process A total of 25 papers met the inclusion criteria and are included in this review. Figure 1 is a flow diagram illustrating the systematic process of identifying the 25 papers included. Figure 1. View largeDownload slide Flowchart illustrating the search process. Figure 1. View largeDownload slide Flowchart illustrating the search process. Results In this review, sensitivity (also called the true positive rate) refers to the ability of the tests to identify non-credible effort when non-credible effort is present. Specificity (also called the true negative rate) refers to the ability of the tests to identify credible effort when credible effort is present. The majority of the studies included in this review involved participants who were deemed to be exerting credible effort due to not being involved in litigation or by virtue of having an established diagnosis of MCI or dementia and therefore having little to no reason to feign impairment (n = 20). This means that the methodology involved administering tests of effort to participants who were already deemed to be exerting credible effort. These studies cannot possibly investigate the sensitivity levels of the effort test(s) in question (there are no true positives present in their samples). They report specificity levels only. The studies (n = 5) which include both participants who are and are not exerting credible effort are able to report both sensitivity and specificity levels with the exception of Schroeder, Peck, Buddin, Heinrichs, and Baade (2012) who used the RBANS Effort Scale as a reference standard but who deemed all of their participants to be exerting credible effort therefore they report specificity levels only. See Tables 1–12 for data extraction which include demographic information and sensitivity and specificity levels where appropriate. This information is listed per PVT. Table 1. Data extraction table for the Test of Memory Malingering (TOMM; Tombaugh, 1996)—all results refer to a cut-off score of <45/40 on TOMM Trial two unless otherwise stated Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) TOMM sensitivitya (%) TOMM specificityb (%) Quality rating score (%) Walter et al. (2014) Dementia (mod/sev) (31) 69.48 (7.86) 15.63 (2.92) RBANS total score 60.7 (7.48) n/a 79 31/40 (78) MCI (28) 66.02 (8.02) 14.68 (2.09) 80.72 (4.47) n/a 91 Controls (30) 71.43 (8.99) 16.33 (3.19) 96.73 (8.61) n/a 100 Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 45 78 37 91 34 95 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 45 100 37 78 34 67 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) n/a 95 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) n/a 36 Dean et al. (2009) Dementia (20) Not reported Not reported MMSE 19.2 (4.4) n/a 45 30/40 (75) Merten, Bossink, & Schmand (2007) AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) n/a 70 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) n/a 100 Teichner & Wagner (2004) Dementia (21) 75.3 (6.1) 13.6 (3.3) MMSE WAIS FSIQ 19.9 (2.8) MMSE 80.6 (12) WAIS n/a 45 24 42 38 40 48 27/40 (68) MCI (36) 70.6 (8.1) 14.2 (3.2) 25.6 (2.5) MMSE 90.8 (14.8) WAIS n/a 45 91.7 42 94.4 40 97.3 Controls (21) 65.6 (8.6) 14.2 (3.6) 28.3 (1.7) MMSE 99.1 (15.3) WAIS n/a 45 100 42 100 40 100 Tombaugh (1997) Dementia (37) 69.48 (7.86) 72.1 (7.6) MMSE Not reported n/a 45 72.9 40 89.2 30/40 (75) Controls (13) 66.02 (8.02) 45.9 (15) 45 100 40 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) TOMM sensitivitya (%) TOMM specificityb (%) Quality rating score (%) Walter et al. (2014) Dementia (mod/sev) (31) 69.48 (7.86) 15.63 (2.92) RBANS total score 60.7 (7.48) n/a 79 31/40 (78) MCI (28) 66.02 (8.02) 14.68 (2.09) 80.72 (4.47) n/a 91 Controls (30) 71.43 (8.99) 16.33 (3.19) 96.73 (8.61) n/a 100 Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 45 78 37 91 34 95 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 45 100 37 78 34 67 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) n/a 95 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) n/a 36 Dean et al. (2009) Dementia (20) Not reported Not reported MMSE 19.2 (4.4) n/a 45 30/40 (75) Merten, Bossink, & Schmand (2007) AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) n/a 70 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) n/a 100 Teichner & Wagner (2004) Dementia (21) 75.3 (6.1) 13.6 (3.3) MMSE WAIS FSIQ 19.9 (2.8) MMSE 80.6 (12) WAIS n/a 45 24 42 38 40 48 27/40 (68) MCI (36) 70.6 (8.1) 14.2 (3.2) 25.6 (2.5) MMSE 90.8 (14.8) WAIS n/a 45 91.7 42 94.4 40 97.3 Controls (21) 65.6 (8.6) 14.2 (3.6) 28.3 (1.7) MMSE 99.1 (15.3) WAIS n/a 45 100 42 100 40 100 Tombaugh (1997) Dementia (37) 69.48 (7.86) 72.1 (7.6) MMSE Not reported n/a 45 72.9 40 89.2 30/40 (75) Controls (13) 66.02 (8.02) 45.9 (15) 45 100 40 100 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination; WAIS FSIQ = Wechsler Adult Intelligence Scale, Full Scale Intelligence Quotient. AD = Alzheimer’s Dementia. Table 1. Data extraction table for the Test of Memory Malingering (TOMM; Tombaugh, 1996)—all results refer to a cut-off score of <45/40 on TOMM Trial two unless otherwise stated Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) TOMM sensitivitya (%) TOMM specificityb (%) Quality rating score (%) Walter et al. (2014) Dementia (mod/sev) (31) 69.48 (7.86) 15.63 (2.92) RBANS total score 60.7 (7.48) n/a 79 31/40 (78) MCI (28) 66.02 (8.02) 14.68 (2.09) 80.72 (4.47) n/a 91 Controls (30) 71.43 (8.99) 16.33 (3.19) 96.73 (8.61) n/a 100 Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 45 78 37 91 34 95 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 45 100 37 78 34 67 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) n/a 95 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) n/a 36 Dean et al. (2009) Dementia (20) Not reported Not reported MMSE 19.2 (4.4) n/a 45 30/40 (75) Merten, Bossink, & Schmand (2007) AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) n/a 70 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) n/a 100 Teichner & Wagner (2004) Dementia (21) 75.3 (6.1) 13.6 (3.3) MMSE WAIS FSIQ 19.9 (2.8) MMSE 80.6 (12) WAIS n/a 45 24 42 38 40 48 27/40 (68) MCI (36) 70.6 (8.1) 14.2 (3.2) 25.6 (2.5) MMSE 90.8 (14.8) WAIS n/a 45 91.7 42 94.4 40 97.3 Controls (21) 65.6 (8.6) 14.2 (3.6) 28.3 (1.7) MMSE 99.1 (15.3) WAIS n/a 45 100 42 100 40 100 Tombaugh (1997) Dementia (37) 69.48 (7.86) 72.1 (7.6) MMSE Not reported n/a 45 72.9 40 89.2 30/40 (75) Controls (13) 66.02 (8.02) 45.9 (15) 45 100 40 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) TOMM sensitivitya (%) TOMM specificityb (%) Quality rating score (%) Walter et al. (2014) Dementia (mod/sev) (31) 69.48 (7.86) 15.63 (2.92) RBANS total score 60.7 (7.48) n/a 79 31/40 (78) MCI (28) 66.02 (8.02) 14.68 (2.09) 80.72 (4.47) n/a 91 Controls (30) 71.43 (8.99) 16.33 (3.19) 96.73 (8.61) n/a 100 Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 45 78 37 91 34 95 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 45 100 37 78 34 67 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) n/a 95 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) n/a 36 Dean et al. (2009) Dementia (20) Not reported Not reported MMSE 19.2 (4.4) n/a 45 30/40 (75) Merten, Bossink, & Schmand (2007) AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) n/a 70 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) n/a 100 Teichner & Wagner (2004) Dementia (21) 75.3 (6.1) 13.6 (3.3) MMSE WAIS FSIQ 19.9 (2.8) MMSE 80.6 (12) WAIS n/a 45 24 42 38 40 48 27/40 (68) MCI (36) 70.6 (8.1) 14.2 (3.2) 25.6 (2.5) MMSE 90.8 (14.8) WAIS n/a 45 91.7 42 94.4 40 97.3 Controls (21) 65.6 (8.6) 14.2 (3.6) 28.3 (1.7) MMSE 99.1 (15.3) WAIS n/a 45 100 42 100 40 100 Tombaugh (1997) Dementia (37) 69.48 (7.86) 72.1 (7.6) MMSE Not reported n/a 45 72.9 40 89.2 30/40 (75) Controls (13) 66.02 (8.02) 45.9 (15) 45 100 40 100 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination; WAIS FSIQ = Wechsler Adult Intelligence Scale, Full Scale Intelligence Quotient. AD = Alzheimer’s Dementia. Table 2. Rey 15-Item Test (RFIT; Rey, 1964)—Bortnik and colleagues (2013) use a cut-off of <9, Rudman and colleagues (2011) use a cut-off of <8 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RFIT sensitivitya (%) RFIT specificityb (%) Quality rating score (%) Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 28 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 100 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG Not reported n/a 85 28/40 (70) Dementia (mod/sev) (22) n/a 27 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RFIT sensitivitya (%) RFIT specificityb (%) Quality rating score (%) Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 28 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 100 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG Not reported n/a 85 28/40 (70) Dementia (mod/sev) (22) n/a 27 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination. Table 2. Rey 15-Item Test (RFIT; Rey, 1964)—Bortnik and colleagues (2013) use a cut-off of <9, Rudman and colleagues (2011) use a cut-off of <8 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RFIT sensitivitya (%) RFIT specificityb (%) Quality rating score (%) Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 28 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 100 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG Not reported n/a 85 28/40 (70) Dementia (mod/sev) (22) n/a 27 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RFIT sensitivitya (%) RFIT specificityb (%) Quality rating score (%) Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 28 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 100 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG Not reported n/a 85 28/40 (70) Dementia (mod/sev) (22) n/a 27 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination. Table 3. Coin in the Hand (CIH; Kapur, 1994)—all studies used a cut-off of ≤7/10 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) CIH specificitya (%) Quality rating score (CCAT) (%) Schroeder et al. (2012) Dementia (45) 77.98 (7.05) 12.76 (3.02) MMSE 21.47 (5.71) 98 31/40 (78) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 100 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 77 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) CIH specificitya (%) Quality rating score (CCAT) (%) Schroeder et al. (2012) Dementia (45) 77.98 (7.05) 12.76 (3.02) MMSE 21.47 (5.71) 98 31/40 (78) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 100 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 77 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination. Table 3. Coin in the Hand (CIH; Kapur, 1994)—all studies used a cut-off of ≤7/10 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) CIH specificitya (%) Quality rating score (CCAT) (%) Schroeder et al. (2012) Dementia (45) 77.98 (7.05) 12.76 (3.02) MMSE 21.47 (5.71) 98 31/40 (78) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 100 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 77 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) CIH specificitya (%) Quality rating score (CCAT) (%) Schroeder et al. (2012) Dementia (45) 77.98 (7.05) 12.76 (3.02) MMSE 21.47 (5.71) 98 31/40 (78) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 100 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 77 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination. Table 4. Word Memory Test (WMT; Green, 2003) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) WMT specificitya (%) Quality rating score (%) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) 71 100 100 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 48 100 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) 21.6 96.7 96.7 Controls (19) 55.8 (7.5) 0 0 n/a 100 Martins & Martins (2010) MCI (21) 71.2 (2) Not reported WMS-III (Logical Memory Subtest) Not reported 67 95.2 95.2 30/40 (75) Merten et al. (2007)b AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 50b n/a 50b 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100b 0b Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) WMT specificitya (%) Quality rating score (%) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) 71 100 100 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 48 100 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) 21.6 96.7 96.7 Controls (19) 55.8 (7.5) 0 0 n/a 100 Martins & Martins (2010) MCI (21) 71.2 (2) Not reported WMS-III (Logical Memory Subtest) Not reported 67 95.2 95.2 30/40 (75) Merten et al. (2007)b AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 50b n/a 50b 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100b 0b aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). bBased on subtests passed/failed—profile analysis not used. CDR = Clinical Dementia Rating; MMSE = Mini-Mental State Examination; AD = Alzheimer’s Dementia. Table 4. Word Memory Test (WMT; Green, 2003) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) WMT specificitya (%) Quality rating score (%) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) 71 100 100 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 48 100 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) 21.6 96.7 96.7 Controls (19) 55.8 (7.5) 0 0 n/a 100 Martins & Martins (2010) MCI (21) 71.2 (2) Not reported WMS-III (Logical Memory Subtest) Not reported 67 95.2 95.2 30/40 (75) Merten et al. (2007)b AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 50b n/a 50b 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100b 0b Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) WMT specificitya (%) Quality rating score (%) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) 71 100 100 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 48 100 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) 21.6 96.7 96.7 Controls (19) 55.8 (7.5) 0 0 n/a 100 Martins & Martins (2010) MCI (21) 71.2 (2) Not reported WMS-III (Logical Memory Subtest) Not reported 67 95.2 95.2 30/40 (75) Merten et al. (2007)b AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 50b n/a 50b 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100b 0b aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). bBased on subtests passed/failed—profile analysis not used. CDR = Clinical Dementia Rating; MMSE = Mini-Mental State Examination; AD = Alzheimer’s Dementia. Table 5. Medical Symptom Validity Test (MSVT; Green, 2004) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produce dementia profile (met Criterion A not Criterion B) MSVT sensitivitya (%) MSVT specificityb (%) Quality rating score (%) Suesse et al. (2015) Dementia (15) Not reported Not reported n/a n/a 19.7 86.7 n/a 86.7 28/40 (70) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) Not reported Not reported Not reported Not reported 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 44 100 n/a 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) Not reported Not reported n/a Not reported Controls (19) 55.8 (7.5) 0 Not reported Not reported n/a Not reported Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65b 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28b Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10) 36 (10) 17 (2) n/a 100 40 60 n/a Howe et al. (2007) Disability WAIS-III FSIQ FSIQ 35/40 (88) Dementia (5) 56.60 (4.95) 11.60 (2.30) 82.20 (5.63) 60 100 n/a 100 MCI (3) 44.33 (19.50) 13.33 (2.31) 89.33 (5.63) 66.7 0 100 n/a Controls (1) 58 13 102 0 n/a n/a n/a No Disability FSIQ Dementia early (13) 73.54 (9.03) 12 (2.42) 89.27 (14.54) 38.46 80 n/a 80 Dementia advanced (18) 76.39 (6.89) 13.83 (2.92) 86.77 (13.45) 83.33 86 n/a 86 MCI (16) 69.50 (9.60) 15.75 (2.93) 100.94 (10.34) 12.5 100 n/a 100 Controls (5) 57.20 (17.33) 15.40 (1.67) 107.80 (10.26) 0 n/a n/a n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produce dementia profile (met Criterion A not Criterion B) MSVT sensitivitya (%) MSVT specificityb (%) Quality rating score (%) Suesse et al. (2015) Dementia (15) Not reported Not reported n/a n/a 19.7 86.7 n/a 86.7 28/40 (70) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) Not reported Not reported Not reported Not reported 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 44 100 n/a 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) Not reported Not reported n/a Not reported Controls (19) 55.8 (7.5) 0 Not reported Not reported n/a Not reported Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65b 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28b Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10) 36 (10) 17 (2) n/a 100 40 60 n/a Howe et al. (2007) Disability WAIS-III FSIQ FSIQ 35/40 (88) Dementia (5) 56.60 (4.95) 11.60 (2.30) 82.20 (5.63) 60 100 n/a 100 MCI (3) 44.33 (19.50) 13.33 (2.31) 89.33 (5.63) 66.7 0 100 n/a Controls (1) 58 13 102 0 n/a n/a n/a No Disability FSIQ Dementia early (13) 73.54 (9.03) 12 (2.42) 89.27 (14.54) 38.46 80 n/a 80 Dementia advanced (18) 76.39 (6.89) 13.83 (2.92) 86.77 (13.45) 83.33 86 n/a 86 MCI (16) 69.50 (9.60) 15.75 (2.93) 100.94 (10.34) 12.5 100 n/a 100 Controls (5) 57.20 (17.33) 15.40 (1.67) 107.80 (10.26) 0 n/a n/a n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cBased on subtests passed/failed—profile analysis not used. CDR = Clinical Dementia Rating; CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination; WAIS FSIQ = Wechsler Adult Intelligence Scale, Full Scale Intelligence Quotient. Table 5. Medical Symptom Validity Test (MSVT; Green, 2004) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produce dementia profile (met Criterion A not Criterion B) MSVT sensitivitya (%) MSVT specificityb (%) Quality rating score (%) Suesse et al. (2015) Dementia (15) Not reported Not reported n/a n/a 19.7 86.7 n/a 86.7 28/40 (70) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) Not reported Not reported Not reported Not reported 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 44 100 n/a 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) Not reported Not reported n/a Not reported Controls (19) 55.8 (7.5) 0 Not reported Not reported n/a Not reported Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65b 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28b Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10) 36 (10) 17 (2) n/a 100 40 60 n/a Howe et al. (2007) Disability WAIS-III FSIQ FSIQ 35/40 (88) Dementia (5) 56.60 (4.95) 11.60 (2.30) 82.20 (5.63) 60 100 n/a 100 MCI (3) 44.33 (19.50) 13.33 (2.31) 89.33 (5.63) 66.7 0 100 n/a Controls (1) 58 13 102 0 n/a n/a n/a No Disability FSIQ Dementia early (13) 73.54 (9.03) 12 (2.42) 89.27 (14.54) 38.46 80 n/a 80 Dementia advanced (18) 76.39 (6.89) 13.83 (2.92) 86.77 (13.45) 83.33 86 n/a 86 MCI (16) 69.50 (9.60) 15.75 (2.93) 100.94 (10.34) 12.5 100 n/a 100 Controls (5) 57.20 (17.33) 15.40 (1.67) 107.80 (10.26) 0 n/a n/a n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produce dementia profile (met Criterion A not Criterion B) MSVT sensitivitya (%) MSVT specificityb (%) Quality rating score (%) Suesse et al. (2015) Dementia (15) Not reported Not reported n/a n/a 19.7 86.7 n/a 86.7 28/40 (70) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) Not reported Not reported Not reported Not reported 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 44 100 n/a 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) Not reported Not reported n/a Not reported Controls (19) 55.8 (7.5) 0 Not reported Not reported n/a Not reported Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65b 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28b Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10) 36 (10) 17 (2) n/a 100 40 60 n/a Howe et al. (2007) Disability WAIS-III FSIQ FSIQ 35/40 (88) Dementia (5) 56.60 (4.95) 11.60 (2.30) 82.20 (5.63) 60 100 n/a 100 MCI (3) 44.33 (19.50) 13.33 (2.31) 89.33 (5.63) 66.7 0 100 n/a Controls (1) 58 13 102 0 n/a n/a n/a No Disability FSIQ Dementia early (13) 73.54 (9.03) 12 (2.42) 89.27 (14.54) 38.46 80 n/a 80 Dementia advanced (18) 76.39 (6.89) 13.83 (2.92) 86.77 (13.45) 83.33 86 n/a 86 MCI (16) 69.50 (9.60) 15.75 (2.93) 100.94 (10.34) 12.5 100 n/a 100 Controls (5) 57.20 (17.33) 15.40 (1.67) 107.80 (10.26) 0 n/a n/a n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cBased on subtests passed/failed—profile analysis not used. CDR = Clinical Dementia Rating; CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination; WAIS FSIQ = Wechsler Adult Intelligence Scale, Full Scale Intelligence Quotient. Table 6. Non-verbal Medical Symptom Validity Test (NV-MSVT; Green, 2008) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) NV-MSVT sensitivitya (%) NV-MSVT specificityb (%) Quality rating score (%) Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65c 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28c Henry et al. (2010) Dementia (21) 59.1 (16.1) 13.1 (3.4) MMSE 25.7 (3.9) 61 61 n/a 100 28/40 (70) Without dementia (n = 44) 15 15 97.7 Controls (50) 62.8 (7.1) 15.8 (3) 28.7 (1.1) 2 2 100 Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10)d 36 (10) 17 (2) n/a 90 40 60 n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) NV-MSVT sensitivitya (%) NV-MSVT specificityb (%) Quality rating score (%) Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65c 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28c Henry et al. (2010) Dementia (21) 59.1 (16.1) 13.1 (3.4) MMSE 25.7 (3.9) 61 61 n/a 100 28/40 (70) Without dementia (n = 44) 15 15 97.7 Controls (50) 62.8 (7.1) 15.8 (3) 28.7 (1.1) 2 2 100 Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10)d 36 (10) 17 (2) n/a 90 40 60 n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cBased on subtests passed/failed – profile analysis not used. dAsked to simulate memory impairment. CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination. Table 6. Non-verbal Medical Symptom Validity Test (NV-MSVT; Green, 2008) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) NV-MSVT sensitivitya (%) NV-MSVT specificityb (%) Quality rating score (%) Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65c 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28c Henry et al. (2010) Dementia (21) 59.1 (16.1) 13.1 (3.4) MMSE 25.7 (3.9) 61 61 n/a 100 28/40 (70) Without dementia (n = 44) 15 15 97.7 Controls (50) 62.8 (7.1) 15.8 (3) 28.7 (1.1) 2 2 100 Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10)d 36 (10) 17 (2) n/a 90 40 60 n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) NV-MSVT sensitivitya (%) NV-MSVT specificityb (%) Quality rating score (%) Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65c 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28c Henry et al. (2010) Dementia (21) 59.1 (16.1) 13.1 (3.4) MMSE 25.7 (3.9) 61 61 n/a 100 28/40 (70) Without dementia (n = 44) 15 15 97.7 Controls (50) 62.8 (7.1) 15.8 (3) 28.7 (1.1) 2 2 100 Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10)d 36 (10) 17 (2) n/a 90 40 60 n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cBased on subtests passed/failed – profile analysis not used. dAsked to simulate memory impairment. CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination. Table 7. Amsterdam Short-Term Memory Test (ASTM; Schagen et al., 1997)—results based on cut-off of 84/85 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) ASTM specificitya (%) Quality rating score (CCAT) (%) Merten et al. (2007) AD dementia (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 10 30/40 (75%) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) ASTM specificitya (%) Quality rating score (CCAT) (%) Merten et al. (2007) AD dementia (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 10 30/40 (75%) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination. Table 7. Amsterdam Short-Term Memory Test (ASTM; Schagen et al., 1997)—results based on cut-off of 84/85 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) ASTM specificitya (%) Quality rating score (CCAT) (%) Merten et al. (2007) AD dementia (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 10 30/40 (75%) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) ASTM specificitya (%) Quality rating score (CCAT) (%) Merten et al. (2007) AD dementia (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 10 30/40 (75%) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination. Table 8. Dot Counting Test (DCT; Rey, 1941) Rudman et al. (2011) results based on “total ungrouped time< total group time”. Dean et al. (2009) and Boone et al. (2002) results based on “mean ungrouped dots counting time + error grouped dot counting time + errors” ≤17 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) DCT specificitya (%) Quality rating score (CCAT) (%) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 90 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 68 Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) 50 30/40 (75) Boone et al. (2002) Dementia (mild) (16) 75.4 (9.3) 12.7 (2.6) MMSE >20 75 21/40 (53) Dementia (mod) 78.1 (10.4) 13 (2.4) 10–20 33.4 Controls 63.5 (8.8) 15.3 (2.4) n/a 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) DCT specificitya (%) Quality rating score (CCAT) (%) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 90 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 68 Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) 50 30/40 (75) Boone et al. (2002) Dementia (mild) (16) 75.4 (9.3) 12.7 (2.6) MMSE >20 75 21/40 (53) Dementia (mod) 78.1 (10.4) 13 (2.4) 10–20 33.4 Controls 63.5 (8.8) 15.3 (2.4) n/a 100 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination. Table 8. Dot Counting Test (DCT; Rey, 1941) Rudman et al. (2011) results based on “total ungrouped time< total group time”. Dean et al. (2009) and Boone et al. (2002) results based on “mean ungrouped dots counting time + error grouped dot counting time + errors” ≤17 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) DCT specificitya (%) Quality rating score (CCAT) (%) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 90 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 68 Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) 50 30/40 (75) Boone et al. (2002) Dementia (mild) (16) 75.4 (9.3) 12.7 (2.6) MMSE >20 75 21/40 (53) Dementia (mod) 78.1 (10.4) 13 (2.4) 10–20 33.4 Controls 63.5 (8.8) 15.3 (2.4) n/a 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) DCT specificitya (%) Quality rating score (CCAT) (%) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 90 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 68 Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) 50 30/40 (75) Boone et al. (2002) Dementia (mild) (16) 75.4 (9.3) 12.7 (2.6) MMSE >20 75 21/40 (53) Dementia (mod) 78.1 (10.4) 13 (2.4) 10–20 33.4 Controls 63.5 (8.8) 15.3 (2.4) n/a 100 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination. Table 9. Finger Tapping Test (FTT; Reitan & Wolfson, 1985) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) FTT specificitya (%) Quality rating score (CCAT) (%) Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) Women Dom ≤28 69 Men Dom≤35 69 30/40 (75) Arnold et al. (2005) Dementia (31) 67.48 (10.95) 13.61 (3.87) Not reported n/a Women Dom ≤28 75 Non-dom ≤25 87 Sum ≤58 80 Difference ≤5 87 Men Dom ≤35 87 Non-dom ≤30 80 Sum ≤66 71 Difference ≤−2 100 25/40 (63) Controls (18) 66.67 (6.51) 17.89 (2.06) Women Dom ≤28 100 Non-dom ≤25 87 Sum ≤58 100 Difference ≤5 100 Men Dom ≤35 100 Non-dom ≤30 100 Sum ≤66 100 Difference ≤−2 90 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) FTT specificitya (%) Quality rating score (CCAT) (%) Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) Women Dom ≤28 69 Men Dom≤35 69 30/40 (75) Arnold et al. (2005) Dementia (31) 67.48 (10.95) 13.61 (3.87) Not reported n/a Women Dom ≤28 75 Non-dom ≤25 87 Sum ≤58 80 Difference ≤5 87 Men Dom ≤35 87 Non-dom ≤30 80 Sum ≤66 71 Difference ≤−2 100 25/40 (63) Controls (18) 66.67 (6.51) 17.89 (2.06) Women Dom ≤28 100 Non-dom ≤25 87 Sum ≤58 100 Difference ≤5 100 Men Dom ≤35 100 Non-dom ≤30 100 Sum ≤66 100 Difference ≤−2 90 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination. Table 9. Finger Tapping Test (FTT; Reitan & Wolfson, 1985) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) FTT specificitya (%) Quality rating score (CCAT) (%) Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) Women Dom ≤28 69 Men Dom≤35 69 30/40 (75) Arnold et al. (2005) Dementia (31) 67.48 (10.95) 13.61 (3.87) Not reported n/a Women Dom ≤28 75 Non-dom ≤25 87 Sum ≤58 80 Difference ≤5 87 Men Dom ≤35 87 Non-dom ≤30 80 Sum ≤66 71 Difference ≤−2 100 25/40 (63) Controls (18) 66.67 (6.51) 17.89 (2.06) Women Dom ≤28 100 Non-dom ≤25 87 Sum ≤58 100 Difference ≤5 100 Men Dom ≤35 100 Non-dom ≤30 100 Sum ≤66 100 Difference ≤−2 90 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) FTT specificitya (%) Quality rating score (CCAT) (%) Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) Women Dom ≤28 69 Men Dom≤35 69 30/40 (75) Arnold et al. (2005) Dementia (31) 67.48 (10.95) 13.61 (3.87) Not reported n/a Women Dom ≤28 75 Non-dom ≤25 87 Sum ≤58 80 Difference ≤5 87 Men Dom ≤35 87 Non-dom ≤30 80 Sum ≤66 71 Difference ≤−2 100 25/40 (63) Controls (18) 66.67 (6.51) 17.89 (2.06) Women Dom ≤28 100 Non-dom ≤25 87 Sum ≤58 100 Difference ≤5 100 Men Dom ≤35 100 Non-dom ≤30 100 Sum ≤66 100 Difference ≤−2 90 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination. Table 10. RBANS Effort Index (EI; Silverberg et al., 2007)—all results refer to a cut-off of >3 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort Index Sensitivitya (%) Effort Index Specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 63 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 93 n/a Burton et al. (2015) AD (90) Not reported Not reported CDR Not reported n/a 51 27/40 (68) Non-AD dementia (55) n/a 54 Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 41 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 89 n/a Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 69.6 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 50 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.608) 21/40 (53) Probable AD (54) n/a Not reported Controls (540) n/a Not reported Duff et al. (2011) AD (126) 76.7 (6.8) <9 years = 12 9–11 years = 14 12 years = 38 13–15 years = 10 >15 years = 26 RBANS total scores 65.9 (5.9) n/a 67.1 31/40 (78) aMCI (72) 72 (82.1) <9 years = 0 9–11 years = 3 12 years = 17 13–15 years = 23 >15 years = 57 92.3 (9.1) n/a 100 Controls (796) 73.4 (5.9) <9 years = 5 9–11 years = 11 12 years = 26 13–15 years = 30 >15 years = 28 95.7 (13.3) n/a 97.1 Barker et al. (2010) Suspect effort (45) 67.1 (10.3) 12 (3) RBANS total index scores IM 57 (16.4) DM 51.6 (14.7) A 60.7 (15.6) L 72 (20.6) VS 70.7 (20.9) n/a 42.2 22/28 (79) Good effort (258) 72.5 (8.8) 12.5 (3.5) IM 75.1 (15.8) DM 76 (19.9) A 81.9 (16.1) L 88.3 (10.6) VS 84.3 (17.7) 95.3 n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort Index Sensitivitya (%) Effort Index Specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 63 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 93 n/a Burton et al. (2015) AD (90) Not reported Not reported CDR Not reported n/a 51 27/40 (68) Non-AD dementia (55) n/a 54 Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 41 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 89 n/a Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 69.6 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 50 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.608) 21/40 (53) Probable AD (54) n/a Not reported Controls (540) n/a Not reported Duff et al. (2011) AD (126) 76.7 (6.8) <9 years = 12 9–11 years = 14 12 years = 38 13–15 years = 10 >15 years = 26 RBANS total scores 65.9 (5.9) n/a 67.1 31/40 (78) aMCI (72) 72 (82.1) <9 years = 0 9–11 years = 3 12 years = 17 13–15 years = 23 >15 years = 57 92.3 (9.1) n/a 100 Controls (796) 73.4 (5.9) <9 years = 5 9–11 years = 11 12 years = 26 13–15 years = 30 >15 years = 28 95.7 (13.3) n/a 97.1 Barker et al. (2010) Suspect effort (45) 67.1 (10.3) 12 (3) RBANS total index scores IM 57 (16.4) DM 51.6 (14.7) A 60.7 (15.6) L 72 (20.6) VS 70.7 (20.9) n/a 42.2 22/28 (79) Good effort (258) 72.5 (8.8) 12.5 (3.5) IM 75.1 (15.8) DM 76 (19.9) A 81.9 (16.1) L 88.3 (10.6) VS 84.3 (17.7) 95.3 n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cAsked to simulate memory impairment. MMSE = Mini-Mental State Examination; RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; CDR = Clinical Dementia Rating aMCI = amnestic; MCI AD = Alzheimer’s Dementia; IM = Immediate Memory; DM = Delayed Memory; A = Attention; L = Language; VS = Visuospatial. Table 10. RBANS Effort Index (EI; Silverberg et al., 2007)—all results refer to a cut-off of >3 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort Index Sensitivitya (%) Effort Index Specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 63 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 93 n/a Burton et al. (2015) AD (90) Not reported Not reported CDR Not reported n/a 51 27/40 (68) Non-AD dementia (55) n/a 54 Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 41 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 89 n/a Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 69.6 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 50 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.608) 21/40 (53) Probable AD (54) n/a Not reported Controls (540) n/a Not reported Duff et al. (2011) AD (126) 76.7 (6.8) <9 years = 12 9–11 years = 14 12 years = 38 13–15 years = 10 >15 years = 26 RBANS total scores 65.9 (5.9) n/a 67.1 31/40 (78) aMCI (72) 72 (82.1) <9 years = 0 9–11 years = 3 12 years = 17 13–15 years = 23 >15 years = 57 92.3 (9.1) n/a 100 Controls (796) 73.4 (5.9) <9 years = 5 9–11 years = 11 12 years = 26 13–15 years = 30 >15 years = 28 95.7 (13.3) n/a 97.1 Barker et al. (2010) Suspect effort (45) 67.1 (10.3) 12 (3) RBANS total index scores IM 57 (16.4) DM 51.6 (14.7) A 60.7 (15.6) L 72 (20.6) VS 70.7 (20.9) n/a 42.2 22/28 (79) Good effort (258) 72.5 (8.8) 12.5 (3.5) IM 75.1 (15.8) DM 76 (19.9) A 81.9 (16.1) L 88.3 (10.6) VS 84.3 (17.7) 95.3 n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort Index Sensitivitya (%) Effort Index Specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 63 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 93 n/a Burton et al. (2015) AD (90) Not reported Not reported CDR Not reported n/a 51 27/40 (68) Non-AD dementia (55) n/a 54 Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 41 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 89 n/a Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 69.6 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 50 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.608) 21/40 (53) Probable AD (54) n/a Not reported Controls (540) n/a Not reported Duff et al. (2011) AD (126) 76.7 (6.8) <9 years = 12 9–11 years = 14 12 years = 38 13–15 years = 10 >15 years = 26 RBANS total scores 65.9 (5.9) n/a 67.1 31/40 (78) aMCI (72) 72 (82.1) <9 years = 0 9–11 years = 3 12 years = 17 13–15 years = 23 >15 years = 57 92.3 (9.1) n/a 100 Controls (796) 73.4 (5.9) <9 years = 5 9–11 years = 11 12 years = 26 13–15 years = 30 >15 years = 28 95.7 (13.3) n/a 97.1 Barker et al. (2010) Suspect effort (45) 67.1 (10.3) 12 (3) RBANS total index scores IM 57 (16.4) DM 51.6 (14.7) A 60.7 (15.6) L 72 (20.6) VS 70.7 (20.9) n/a 42.2 22/28 (79) Good effort (258) 72.5 (8.8) 12.5 (3.5) IM 75.1 (15.8) DM 76 (19.9) A 81.9 (16.1) L 88.3 (10.6) VS 84.3 (17.7) 95.3 n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cAsked to simulate memory impairment. MMSE = Mini-Mental State Examination; RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; CDR = Clinical Dementia Rating aMCI = amnestic; MCI AD = Alzheimer’s Dementia; IM = Immediate Memory; DM = Delayed Memory; A = Attention; L = Language; VS = Visuospatial. Table 11. RBANS Effort Scale (ES; Novitski, Steele, Karantzoulis & Randolph)—all results refer to a cut-off of <12 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort scale sensitivitya (%) Effort scale specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 42 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 71 n/a Burton et al. (2015) AD dementia (53) Not reported Not reported CDR Not reported n/a 96 69 27/40 (68) Non-AD dementia (36) n/a Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 81 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 88 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.908) 21/40 (53) probable AD (54) Not reported Controls (540) 84.9 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort scale sensitivitya (%) Effort scale specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 42 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 71 n/a Burton et al. (2015) AD dementia (53) Not reported Not reported CDR Not reported n/a 96 69 27/40 (68) Non-AD dementia (36) n/a Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 81 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 88 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.908) 21/40 (53) probable AD (54) Not reported Controls (540) 84.9 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). RBANS = Repeatable Battery for the Assessment of Neuropsychological Status. bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CDR = Clinical Dementia Rating. cAsked to simulate memory impairment. AD = Alzheimer’s Dementia. Table 11. RBANS Effort Scale (ES; Novitski, Steele, Karantzoulis & Randolph)—all results refer to a cut-off of <12 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort scale sensitivitya (%) Effort scale specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 42 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 71 n/a Burton et al. (2015) AD dementia (53) Not reported Not reported CDR Not reported n/a 96 69 27/40 (68) Non-AD dementia (36) n/a Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 81 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 88 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.908) 21/40 (53) probable AD (54) Not reported Controls (540) 84.9 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort scale sensitivitya (%) Effort scale specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 42 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 71 n/a Burton et al. (2015) AD dementia (53) Not reported Not reported CDR Not reported n/a 96 69 27/40 (68) Non-AD dementia (36) n/a Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 81 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 88 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.908) 21/40 (53) probable AD (54) Not reported Controls (540) 84.9 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). RBANS = Repeatable Battery for the Assessment of Neuropsychological Status. bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CDR = Clinical Dementia Rating. cAsked to simulate memory impairment. AD = Alzheimer’s Dementia. Table 12. Reliable Digit Span (RDS; Greiffenstein et al., 1994)—all results refer to a cut-off of ≤6 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RDS specificitya (%) Quality rating score (CCAT) (%) Zenisek et al. (2016) AD (133) 72.6 (7.8) 14.8 (2.9) MoCA 21 (4.8) 80.5 23/40 (58) VAD (8) 75 DLB (27) 85.2 FTD (15) 73.3 MCI (168) 94.6 Loring et al. (2016) AD (178) 75.7 (7.5) Not reported MMSE 23.3 (2) 87 31/40 (78) aMCI (365) 74.9 (7.2) 27 (1.8) 96 Controls (206) 76 (5) 29.1 (1) 97 Kiewel et al. (2012) Dementia (mild) 74.6 (8.8) 14.5 (2.7) MMSE 23.4 (3.1) 89 30/40 (75) Dementia (mod) 76.5 (9.4) 14.2 (2.7) 16.8 (2.9) 76 Dementia (sev) 71.2 (10.6) 13.5 (2.7) 7.7 (3.4) 17 Dean et al. (2009) Dementia (172) Not reported Not reported MMSE 19.2 (4.4) 70 30/40 (75) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RDS specificitya (%) Quality rating score (CCAT) (%) Zenisek et al. (2016) AD (133) 72.6 (7.8) 14.8 (2.9) MoCA 21 (4.8) 80.5 23/40 (58) VAD (8) 75 DLB (27) 85.2 FTD (15) 73.3 MCI (168) 94.6 Loring et al. (2016) AD (178) 75.7 (7.5) Not reported MMSE 23.3 (2) 87 31/40 (78) aMCI (365) 74.9 (7.2) 27 (1.8) 96 Controls (206) 76 (5) 29.1 (1) 97 Kiewel et al. (2012) Dementia (mild) 74.6 (8.8) 14.5 (2.7) MMSE 23.4 (3.1) 89 30/40 (75) Dementia (mod) 76.5 (9.4) 14.2 (2.7) 16.8 (2.9) 76 Dementia (sev) 71.2 (10.6) 13.5 (2.7) 7.7 (3.4) 17 Dean et al. (2009) Dementia (172) Not reported Not reported MMSE 19.2 (4.4) 70 30/40 (75) aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; aMCI = amnestic MCI AD = Alzheimer’s Dementia; VAD = Vascular Dementia; DLB = Dementia with Lewy Bodies; FTD = Frontotemporal Dementia. Table 12. Reliable Digit Span (RDS; Greiffenstein et al., 1994)—all results refer to a cut-off of ≤6 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RDS specificitya (%) Quality rating score (CCAT) (%) Zenisek et al. (2016) AD (133) 72.6 (7.8) 14.8 (2.9) MoCA 21 (4.8) 80.5 23/40 (58) VAD (8) 75 DLB (27) 85.2 FTD (15) 73.3 MCI (168) 94.6 Loring et al. (2016) AD (178) 75.7 (7.5) Not reported MMSE 23.3 (2) 87 31/40 (78) aMCI (365) 74.9 (7.2) 27 (1.8) 96 Controls (206) 76 (5) 29.1 (1) 97 Kiewel et al. (2012) Dementia (mild) 74.6 (8.8) 14.5 (2.7) MMSE 23.4 (3.1) 89 30/40 (75) Dementia (mod) 76.5 (9.4) 14.2 (2.7) 16.8 (2.9) 76 Dementia (sev) 71.2 (10.6) 13.5 (2.7) 7.7 (3.4) 17 Dean et al. (2009) Dementia (172) Not reported Not reported MMSE 19.2 (4.4) 70 30/40 (75) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RDS specificitya (%) Quality rating score (CCAT) (%) Zenisek et al. (2016) AD (133) 72.6 (7.8) 14.8 (2.9) MoCA 21 (4.8) 80.5 23/40 (58) VAD (8) 75 DLB (27) 85.2 FTD (15) 73.3 MCI (168) 94.6 Loring et al. (2016) AD (178) 75.7 (7.5) Not reported MMSE 23.3 (2) 87 31/40 (78) aMCI (365) 74.9 (7.2) 27 (1.8) 96 Controls (206) 76 (5) 29.1 (1) 97 Kiewel et al. (2012) Dementia (mild) 74.6 (8.8) 14.5 (2.7) MMSE 23.4 (3.1) 89 30/40 (75) Dementia (mod) 76.5 (9.4) 14.2 (2.7) 16.8 (2.9) 76 Dementia (sev) 71.2 (10.6) 13.5 (2.7) 7.7 (3.4) 17 Dean et al. (2009) Dementia (172) Not reported Not reported MMSE 19.2 (4.4) 70 30/40 (75) aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; aMCI = amnestic MCI AD = Alzheimer’s Dementia; VAD = Vascular Dementia; DLB = Dementia with Lewy Bodies; FTD = Frontotemporal Dementia. The majority of the studies included in this review therefore report specificity levels but not sensitivity levels. The results of the studies included in this review will be reported by effort test and grouped by purpose-built versus embedded effort tests: Purpose-Built PVTs Test of Memory Malingering (TOMM; Tombaugh, 1996). Rey 15-Item Test (RFIT; Rey, 1964). The Coin in the Hand (CIH; Kapur, 1994). Word Memory Test (WMT; Green, 2003). Medical Symptom Validity Test (MSVT; Green, 2004). Non-Verbal Symptom Validity Test (NV-MSVT; Green, 2008). Amsterdam Short Memory Test (ASTM; Schagen, Schmand, de Sterke &, Lindeboom, 1997). Dot Counting Test (DCT; Rey, 1941). Finger Tapping Test (FTT; Reitan & Wolfson, 1985). Embedded PVTs Repeatable Battery for the Assessment of Neurological Status (RBANS; Randolph et al., 1998) Effort Index (EI; Silverberg et al., 2007). Effort Scale (ES; Novitski et al., 2012). Two novel indices (PVI and CRIER) (Paulson, Horner, & Bachman, 2015). Reliable Digit Span (RDS; Greiffenstein, Baker, & Gola, 1994). Note that the study by Dean and colleagues (2009) included in this review investigated a total of 18 stand-alone and embedded effort tests. It was out with the scope of this review to include all of these PVTs however those which have also been investigated by other studies have been included. These are TOMM, RFIT, DCT and RDS. Purpose-Built PVTs Test of Memory Malingering (TOMM; Tombaugh, 1996) Seven of the 25 papers included in this review investigated the use of the TOMM, one of the most widely used PVTs. The results of the studies can be found in Table 1. The TOMM is a picture-recognition, forced-choice, purpose-designed effort test consisting of two learning trials and an optional retention trial. A cut-off of <45 for Trial 2 suggests that a score lower than this is indicative of poor effort. Across the seven studies, pass rates for the dementia groups (Trial 2 <45) ranged from a low of 24% (Teichner & Wagner, 2004) to a high of 95% (Rudman, Oyebode, Jones, & Bentham, 2011). Only two of the seven studies investigated the utility of the TOMM in MCI samples (Teichner & Wagner, 2004; Walter, Morris, SwierVosnos, & Pliskin, 2014). Both studies found similar pass rates for these samples (91.7% and 90.3%, respectively). Drawing comparisons between the results of these studies is compromised to an extent, because they use different criteria for diagnosing dementia (DSM-III, DSM-IV, and the ADRDA-NINDS) and they also assess cognitive function using different tools (five report MMSE scores, one uses the RBANS and one the CAMCOG). This is important because one reason for the discrepancy in results across studies might be that the samples include individuals with significantly different levels of cognitive function. The difference in results reported by Tombaugh (1997) and Teichner and Wagner (2004) may be explained by dementia severity. Tombaugh states that 4/37 dementia participants (i.e., 10% of their dementia sample) who scored below 40 on the TOMM, had MMSE scores of 7, 15, 16, and 19. The paper does not, however, give any detail about the MMSE scores of the rest of the sample (presumably the remaining participants all of whom scored >45 in this sample had MMSE scores of >19). In Teichner and Wagner’s (2004) sample, however, 9/21 (i.e., 42.9% of their dementia sample), had MMSE scores lower than 19. It may therefore be that Teichner and Wagner’s (2004) sample was more cognitively impaired than that of Tombaugh’s (1997). Rudman, and colleagues (2011) found a specificity of 95% for the TOMM, however this was in a sample of mildly impaired dementia participants. Specificity dropped to 36% in their moderate to severely impaired sample. Bortnik, Horner, and Bachman (2013), Teichner and Wagner (2004), and Tombaugh (1997) all give data for alternative cut-offs. A cut-off of 40 produced a specificity of 89.2% in Tombaugh’s sample however the same cut-off yielded only 48% specificity in Teichner and Wagner’s dementia sample (cf. 97.3% of their MCI group). In the Bortnik et al. (2013) good effort dementia sample, the TOMM reached 95% specificity when the cut-off was lowered to 34 There are also some flaws in the reporting of results across studies. Tombaugh (1997), who received a score of 30/40 on the CCAT, states that ‘a cutting score of 45 on Trial 2 produced a high level of specificity. It correctly classified 95% of all non-demented patients (91% of all patients) as non-malingering’ (p. 265). As previously mentioned however, 89.1% of Tombaugh’s (1997) dementia sample passed the TOMM but only when a cut-off score of <40 was used. This drops to 72.9% with the recommended cut-off of <45, meaning that approximately one in four of their dementia patients were incorrectly classified as putting forth non-credible effort. Additionally, with the exception of Bortnik and colleagues (2013), sample sizes across studies were small. Rey 15-Item Test (RFIT; Rey, 1964) Alongside the TOMM, the RFIT is one of the most widely used effort tests in clinical practice (Slick, Tan, Strauss, & Hultsch, 2004). The task consists of studying a card for 10 s which has five rows of three characters. The test consists of a free-recall and an optional recognition trial. A score lower than 9 on the free-recall trial and a score lower than 20 on the combination equation are said to be indicative of non-credible effort (Boone, Salazar, Lu, Warner-Chacon, & Razani, 2002). The results of studies investigating the RFIT can be found in Table 2. Bortnik and colleagues (2013) reported a high sensitivity to non-credible effort in their “suspect effort” group (100%) but a very low specificity (28%) in their good effort group. Rudman and colleagues (2011) found a similar specificity level (27%) for their moderate/severe dementia group. The studies use different tools to assess cognitive impairment (MMSE and CAMCOG) however research suggests these screens are highly correlated (Heinik, Solomesh, & Berkman, 2004); therefore, it was possible to note that both Rudman and Bortnik’s dementia samples were equally impaired (mean CAMCOG 62.45, mean MMSE 20.8). Rudman found far better specificity in their mildly impaired sample (85% specificity, mean MMSE 20.8). Both studies performed similarly on the quality rating checklists (70%). The Coin in the Hand (CIH; Kapur, 1994) The Coin in the Hand Test (CIH) was developed to be a “simple, brief test designed to detect the presence of malingering in patients who are suspected of simulating poor memory performance” (Kapur, 1994, p. 385). It is a stand-alone, forced-choice test in which the clinician holds a coin in their right or left hand in front of the examinee who then closes their eyes and counts backwards from 10 before opening their eyes to report which hand the coin is in. A score of 7 or less out of 10 trials is used as the cut-off for this test. See Table 3 for the results of studies investigating the CIH. Two of the papers included in this review examined the utility of the CIH. Schroeder and colleagues (2012) used a sample of 45 inpatients with a diagnosis of dementia. The Schroeder study performed fairly well on the CCAT (31/40). In order to ensure that their sample would put forth adequate effort on the CIH, Schroeder excluded participants involved in litigation or who were collecting disability payments and they also excluded any participant failing the RBANS Effort Scale. Using a cut-off score of ≤7 resulted in a specificity of 98% in the Schroeder sample. Using the same cut-off, Rudman et al. (2011) found specificity of 100% in their mild dementia sample compared to 77% in the moderate/severe sample. Specificity therefore is high with a CIH cut-off of ≤7 as long as the examinee is not too cognitively impaired. Word Memory Test (WMT; Green, 2003) The WMT, MSVT, and NV-MSVT, all devised by Green, are PVTs which are a departure from the traditional pass/fail effort tests in that they use profile analysis to determine an individual’s level of effort. They are based on a hierarchical approach in line with the criteria devised by Slick et al. (1999). On these PVTs, a participant’s score is first compared against a cut-off (a pass/fail approach) and then for those participants who fail, their profile of scores over several subtests is analyzed. These tests are unique in that they allow the examiner to distinguish between failure due to poor effort and failure due to cognitive impairment. Green states that on the WMT, MSVT, and NV-MSVT, people with genuine cognitive impairment produce a specific profile of results, different from the pattern of results produced by those exerting non-credible effort. To differentiate between the two, the difference between the mean scores on the easy and hard subtests is calculated. Individuals with a diagnosis of dementia invariably show easy-hard differences of at least 20 points on these subtests, whereas such significant differences are rarely present in people asked to feign impairment. This pattern of results is known as the “dementia profile.” These three effort tests are described and the literature evaluated in turn. The WMT is a word-list learning task that involves learning a list of 20 word pairs which are presented twice, either on a computer screen or spoken aloud by the examiner (as in the original oral version of the test). It contains multiple subtests of which the first two are specifically designed to measure effort (Immediate and Delayed Recognition), the remaining subtests are conventional memory subtests. As stated earlier, the profile of scores on the WMT subtests (particularly the difference between the effort subtests and the conventional memory subtests) can indicate whether individuals fail the test due to insufficient effort or to the severity of their cognitive impairment. The results of the studies investigating the WMT can be found in Table 4. Merten and colleagues (2007) found that while all their controls passed the WMT effort subtests, almost all of the AD participants failed it (90% failed both the Immediate and Delayed Recognition trials). It is important to note however, that the authors were not able to analyze the profile of scores on the two effort subtests against those of the conventional memory tests because normative data for a Dutch population were not available at the time of the study. This is a significant limitation of the Merten et al. (2007) study because the researchers were only able to look at whether participants passed or failed the effort subtests and were not able to look at the profile of their scores to investigate whether they indicated a “dementia profile”. Green, Montijo, and Brockhaus (2011) found that 41/65 (63%) of their dementia sample and 13/60 (21.6%) of their MCI sample failed the easy subtests of the WMT. Using profile analysis, however, they found that every participant with dementia exhibited a “dementia profile” meaning there were no false positives. Regarding the MCI sample, only 2 of the 11 participants who failed the easy subtests of the WMT, indicated a profile suggestive of poor effort, which represents a false-positive rate of 3.3% for the total sample. The study however scored 28/40 on the CCAT due to inadequate reporting such as missing demographic data. It should perhaps also be noted that the participants were not screened for potential financial incentives, meaning that it cannot be concluded that the two participants who generated a poor effort profile were real false-positives. Martins and Martins (2010) found that 67% of their MCI sample failed the easy subtests of the WMT however 95% produced a dementia profile therefore were not misclassified as exerting non-credible effort. Medical Symptom Validity Test (MSVT; Green, 2004) The MSVT is a shorter, modified and easier version of the WMT. Five of the papers in this review examined the utility of the MSVT in people with dementia, MCI, cognitively intact controls and volunteers asked to simulate dementia and the results of these studies can be found in Table 5. Two of the papers were able to report sensitivity levels of 60% (simulators) and 100% (suspect effort MCI sample). Performance on the easy subtests was variable across the studies from only 12.5% of Howe, Anderson, Kaufman, Sachs, and Loring (2007) MCI sample failing the subtests compared to 100% of Singhals’ simulator sample. More importantly however is that by using profile analysis, specificity levels for the MSVT across the four studies ranged from 80% to 100%, meaning that very few individuals were misclassified as exhibiting poor effort. The exception was Rudman et al. (2011) who solely calculated effort based on whether participants had passed or failed the easy subtests. They did not use profile analysis. Although these results are promising, they should be treated as preliminary as the studies involved very small sample sizes. Non-Verbal Medical Symptom Validity Test (NV-MSVT; Green, 2008) The NV-MSVT is the non-verbal equivalent of the MSVT. Three studies were found to investigate the diagnostic accuracy of this PVT in dementia and healthy controls and the results of these can be found in Table 6. As noted with the MSVT, Rudman et al. (2011) found low specificity of the NV-MSVT (33% in their overall dementia sample), however they did not use profile analysis therefore their results are not complete or accurate. Henry, Merten, Wolf, and Harth (2010) found specificity of 100% in their controls and dementia sample and 97.7% in their non-dementia (neurological) sample whilst Singhal and colleagues (2009) found 100% specificity for their institutionalized dementia patients. Interestingly, Singhal’s entire dementia sample failed the effort subtests of the NV-MSVT; however, they all showed a “dementia profile”; therefore, they were not misclassified as malingering. They were also a particularly impaired sample (average MMSE of 15.5). Amsterdam Short Memory Test (ASTM; Schagen et al., 1997) The ASTM is a forced-choice test in which five examples from a category (e.g. animals, colors etc.) are read aloud by the examinee. A relatively simple mathematical problem is then presented to the examinee after which time another five words from the same category are presented. The examinee’s task is to recognize which three words are identical to those in the first list. The test maximum score is 90 and the cut-off is 84/85. Merten et al. (2007) found that all of their controls passed the ASTM however only 10% of their Alzheimer’s dementia participants passed the test (i.e., specificity, 10%) (see Table 7). Given that 70% of the same AD sample passed the TOMM, it would appear that the ASTM is unlikely to be an appropriate choice of PVT for individuals with cognitive impairment due to a possible dementia because the false-positive rate is likely to be high. Dot Counting Test (DCT; Rey, 1941) The DCT is a task in which the examinee is presented with twelve cards containing different numbers of dots. The first six cards contain dots arranged in a random order and the following six cards contain grouped dots. Examinees are asked to count the dots as quickly as possible. The three studies investigating the DCT in dementia and control samples used different scoring methods (see Table 8). Dean et al. (2009) and Boone et al. (2002) used a scoring system whereby the mean ungrouped dot counting time, the mean grouped dot counting time and the error score are summed. They found poor specificity for their dementia samples (33.4%–75%) but perfect specificity for their healthy controls. Rudman et al. (2011) used the scoring recommended by Lezak, Howieson, Loring, and Fischer (2004) which is that suspect effort is considered if the time taken to count the grouped dots is equal to or more than the time required to count the ungrouped dots. They found good specificity (90%) for their mild dementia sample but poor specificity (68%) for their moderate/severe sample. They used this scoring method because the combined score uses two measures of reaction time which they proposed to be inappropriate index to use with dementia samples as individuals with dementia typically experience a reduction in their processing skills. Finger Tapping Test (FTT; Reitan & Wolfson, 1985) The Finger Tapping Test (FTT) is used in neuropsychology both as part of the Halstead–Reitan Neuropsychological Test Battery (HRNB) and as a stand-alone PVT. See Table 9 for the results of the studies investigating the FTT in dementia and controls. The recommended cut-offs for dominant-hand finger tapping (women - ≤28, men ≤35) reveal poor specificity for the dementia groups across the two papers included in this review (69%–87%). Arnold et al. (2005), however, provide various cut-offs for dominant hand, non-dominant hand, summed hands, and difference between hands. They found 100% specificity for male dementia participants using a difference score of ≤−2 and 87% specificity for female dementia participants using a difference score of ≤5. Further analysis revealed differences in specificity values by dementia subgroup such that the dominant hand cut-off of ≤28 for women with Alzheimer’s disease (AD) was 83% while for females with non-AD dementias, the specificity reduced to 64%. Similarly, a cut-off of >41 for the dominant hand identified 100% of men with AD dementia while only 37% of men with non-AD dementias achieved the same score. Embedded PVTs The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS; Randolph et al., 1998) The RBANS is a widely used neurocognitive battery commonly used in the assessment of dementia. Two RBANS embedded measures of effort have been developed: the Effort Index (EI; Silverberg et al., 2007) and the Effort Scale (ES; Novitski et al., 2012). Seven of the eight studies which investigated these embedded indices, examined the utility of the EI, four examined the utility of the ES and one paper compared both the EI and the ES against two novel RBANS embedded indices. RBANS Effort Index (EI; Silverberg et al., 2007) The EI combines performance on two subtests (Digit Span and List Recognition) to produce an “effort index”. A score of greater than 3 is suggestive of non-credible effort. In the development of the EI, it was found that very poor performance on both these subtests was extremely rare in a mixed clinical sample of patients with neurological disorders. See Table 10 for results of studies investigating the EI. All four of the studies which use a reference standard in order to divide participants into credible and non-credible effort groups, investigated the use of the EI. Sensitivity levels for the EI were 0.50, 0.89, 0.93, and 0.95. Unlike the TOMM studies, dementia severity does not appear to explain the differing sensitivity levels found for the EI. Bortnik et al. (2013) who report a sensitivity level of only 0.50 in their “suspect effort” dementia sample also report that this group had a mean MMSE score of 17.9. Compare this to Paulson and colleagues (2015) who found a sensitivity level of 0.93 in a dementia sample with a mean MMSE score of 23.1. It should be noted, however, that the Bortnik et al. (2013) study included a very small sample (n = 9) and scored relatively poorly on the STARD (20/28) due to inadequate reporting. Specificity levels were reported by all seven papers and range from a low of 0.41 (Dunham, Shadi, Sofko, Denney, & Calloway, 2014) to a relative high of 0.69 (Bortnik et al., 2013). Only controls and MCI samples produced acceptable levels of specificity on the EI. RBANS Effort Scale (ES; Novitski et al., 2012) The RBANS Effort Scale is based on the premise that when an individual has genuine memory impairment, their performance on free-recall tasks (List Recall, Story Recall, and Figure Recall subtests) will decline to close to zero before decline in List Recognition is seen. The authors of the ES propose a cut-off of <12 as being suggestive of non-credible effort (the ES calculation is: List Recognition – (List Recall + Story Recall + Figure Recall)) + Digit Span). See Table 11 for studies investigating the ES. The studies investigating the ES scored relatively poorly on the quality checklists due to inadequate and/or missing information making it difficult to examine the results across studies. In the original validation study, Novitski et al. (2012) compared dementia and MCI participants with a poor effort group of mild head injury participants, they report an impressive area under the curve (AUC) of 0.908. The paper scored poorly, however, on the CCAT (21/40) due to inadequate information given regarding data collection, inclusion and exclusion criteria and participant demographic information. Burton and colleagues (2015) compared the ES in AD and non-AD dementias. They found an impressively high specificity level of 0.96 in their AD sample; however, this fell to 0.69 in their non-AD sample. The authors conclude that the ES may be an appropriate effort index to use when assessing effort level in people with a dementia of the Alzheimer’s type, however in clinical practice, effort tests are most likely to be given during the diagnostic process when a person’s diagnosis is as yet unknown. It does raise the issue that the ES is based on the premise that a person’s performance on tests of free recall will decline before their performance on tests of recognition. This profile of impairment is more likely to be seen in AD, which is characterized by a deficit in episodic memory, than in non-AD dementias. Paulson et al. (2015) and Dunham et al. (2014) investigated the ES in both good and suspect effort groups. They found a sensitivity of 0.71 and 0.88 and specificity levels of 0.42 and 0.81, respectively. It is not clear why the studies found very different specificity levels and due to inadequate reporting by the studies it was impossible to investigate whether type of dementia had a bearing on the discrepancy in the results found (i.e., if the reason for the high failure rate in Paulson’s good effort group was due to the majority having a non-AD dementia). Performance Validity Index (PVI; Paulson et al., 2015) and Charleston Revised Index of Effort for RBANS (CRIER; Paulson et al., 2015) Paulson and colleagues evaluated the EI and ES against two novel RBANS embedded indices of effort, the PVI and the CRIER. The PVI cut-off for detecting invalid responding is <42 and is calculated as follows: RBANS PVI: List recall + story recall + figure recall + digit span + list recognition The CRIER cut-off for detecting invalid responding is <24 and is calculated as follows: RBANS CRIER: list recall + story recall + figure recall + digit span + list recognition − GDS The PVI was found to have a sensitivity of 0.82, a specificity of 0.77, and an AUC of 0.90 whilst the CRIER had a sensitivity of 0.84, a specificity of 0.90, and an AUC of 0.94. These are promising results and warrant further research. Reliable Digit Span (RDS; Greiffenstein et al., 1994) Greiffenstein and colleagues (1994) originally derived the RDS from the Digit Span subtest of the Wechsler Adult Intelligence Scale–Revised (Wechsler, 1981) by “summing the longest string of digits repeated without error over two trials under both forward and backward conditions” (pp. 219–220). Table 12 illustrates the results of studies investigating the RDS. RDS specificity was found to be greatly affected by severity of cognitive impairment. It had high specificity for Loring’s dementia (87%), MCI (96%), and control samples (97%) and also for Zenisek’s (2016) MCI sample (94.6%) whilst Kiewel, Wisdom, Bradshaw, Pastorek and Strutt (2012) found high specificity for their mild dementia sample (89%). All of these samples had MMSE scores of 23 or more (except for Zenisek et al., 2016 who used the MoCA). In contrast, with Kiewel’s more impaired groups, the RDS yielded an unacceptably high level of false positives similar to those in the equally impaired Dean et al. (2009) study. Zenisek et al. (2016) divided their sample into subgroups based on type of dementia diagnosed and found differences in specificity levels with a high of 85.2 for dementia with Lewy bodies sample and a low of 73.3 for their frontotemporal dementia sample. Discussion This review included 25 papers examining the diagnostic accuracy of 14 embedded and stand-alone tests of effort in dementia and MCI samples. In particular this review sought to establish which PVTs were most sensitive to non-credible effort whilst being insensitive to the cognitive impairment seen in individuals who meet criteria for these diagnoses. The effort tests which were found to be most sensitive to non-credible effort whilst being least sensitive to dementia-related cognitive impairment were the three PVTs devised by Green (2003, 2004, 2008). The WMT, MSVT, and NV-MSVT go beyond the pass/fail approach of traditional effort tests and instead use profile analysis to determine if the pattern of results which an examinee produces are indicative of poor effort or if they show a “dementia profile.” The vast majority of the studies which investigated these tests found 100% specificity. The only studies which found low levels of specificity for these PVTs were those which calculated Criterion A only and did not use profile analysis to determine effort level (i.e., determined effort level on whether the participants scored below cut-off on the effort tests but did not determine whether a dementia profile was present). The WMT, MSVT, and NV-MSVT therefore appear to be the most appropriate effort tests for use in cognitive assessment when a dementia is queried. These results should be taken as provisional however because, although the evidence is promising there is not a wealth of literature to draw from. It should also be noted that producing a “dementia profile” is not in itself proof of adequate effort and that clinicians should aim to employ a multi-method approach to effort testing such as that devised by Slick et al. (1999) to highlight any inconsistencies between PVT results and information gathered from other sources. Some of the other tests explored in this review were found to have acceptable specificity levels when used with MCI or mild dementia samples such as the TOMM, the Coin in the Hand, and the RDS. These PVTs do, however, lose specificity with more impaired samples. Methodological Limitations of Effort Testing Literature Compared with other areas of research in clinical neuropsychology, effort testing research faces significant methodological challenges because no “gold-standard” exists with which to reliably determine performance validity. Five of the 25 papers included in this review attempted to independently assess effort by use of a reference standard (three used the TOMM, one used the MSVT, and one used the RBANS Effort Scale). The remaining 20 papers either excluded participants who may have had an incentive to feign impairment or they assumed good effort by virtue of the participants having a diagnosis of dementia. This makes it difficult to know what the true false-positive rate actually is. Diagnostic tests should be evaluated in samples that are representative of those with whom the test will be used in practice. The majority of the studies included in this review use a methodology whereby participants with an established dementia are compared to healthy controls. This is likely to lead to bias because the participants included have a more advanced stage of the disease (in this case dementia) than studies using a clinical sample of consecutive referrals to memory clinics. Indeed there appears to be a positive correlation between PVT specificity and severity of cognitive impairment, such that as scores on cognitive tests decrease, so too does the specificity level of a PVT. Also, very few of the studies included samples with a diagnosis of MCI, a population of importance when evaluating the diagnostic accuracy of effort tests in older adults presenting with memory difficulties. Additionally, very few of the studies included in this review were able to assess sensitivity levels because they only included participants who were deemed to exert credible effort from the outset, either due to not being involved in litigation/claiming disability benefits or simply by virtue of having a diagnosis of dementia. Finally, the studies included in this review largely approach the subject of effort in its “malingering” definition whereby examinees are deemed to be feigning impairment. As discussed previously, indications of poor or atypical motivation are not always the result of deliberate malingering, rather there are many reasons for an individual to put forth less than credible effort such as low mood, stress, conversion disorder, medication side effects and fatigue amongst others. The majority of the studies in this review did not assess for these factors. Methodological Limitations of the Current Review This systematic review faced some methodological limitations. First, it was out with the scope of the review to include every study which has investigated the diagnostic utility of PVTs in dementia samples. The current study focused on papers which included dementia/MCI samples as their primary interest. There are, however, other studies which include a dementia sample alongside other clinical samples. Additionally, as previously mentioned, it was also out with the scope of the current review to examine every PVT investigated by the papers included therefore only the PVTs which are known to be most used in clinical practice were reviewed. Finally, some of the studies examined the performance of the PVTs across different cut-offs. It was not possible to review each of these cut-offs therefore those most used in clinical practice were evaluated. Conclusions Future research on the diagnostic accuracy of PVTs in older adults should aim to focus on the recruitment of consecutive referrals to memory clinics and should employ a multi-method approach such as that proposed by Slick et al. (1999). As part of the cognitive test battery, the participants should receive a reference standard (such as the MSVT or NV-MSVT) and the PVT of interest (the index test). The index test should only be calculated once the final diagnosis is known. This method would allow for both sensitivity and specificity of the PVT in question to be investigated because both good effort and suspect effort participants would be included. Future research should also seek to review the diagnostic utility of PVTs across various cut-offs in MCI/dementia samples. Future research may also seek to further evaluate the use of the two new RBANS embedded indices (PVI and CRIER) created by Paulson et al. (2015) as these showed good potential and the RBANS is a commonly used tool in older adult memory clinics. It is also important for future research to look at subtypes of dementia and how profiles of impairment impact PVT performance. It is likely that some of the variation in performance seen across the different studies may be partially accounted for not just by dementia severity but by dementia subtype. Burton et al. (2015) touched on this issue when they found that the Effort Scale had significantly higher specificity in their Alzheimer’s sample (96%) compared to their non-Alzheimer sample (69%). Following the evaluation of the studies in this review, tests which take a hierarchical approach to effort testing such as the WMT, MSVT and the NV-MSVT may be the best PVTs to use in clinical practice given that these tests have been found to be particularly robust in dementia samples (i.e., they have very low false-positive rates). 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Effort Testing in Dementia Assessment: A Systematic Review

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Oxford University Press
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© The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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0887-6177
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Abstract

Abstract Objective Interpretation of neuropsychological test data is only valid when appropriate effort has been exerted. Research, however, suggests that neuropsychologists do not always formally test for effort and that this may especially be the case in the context of dementia assessment. This review systematically examined the literature that has investigated the use of both purpose-built and embedded effort-sensitive indices in dementia, mild cognitive impairment (MCI), and healthy control samples. The aim was to determine which tests of effort are most sensitive to suboptimal effort and least sensitive to the type of cognitive impairment seen in dementia. Methods A systematic search of databases was conducted to October 2017. There was no start date. Results Twenty-five studies were included for review. The studies were divided into two categories according to methodology. One category of studies (n = 5) was reviewed using a tailored methodological quality rating checklist whilst the remaining studies (n = 20) were reviewed using the Crowe Critical Appraisal Tool (CCAT). Conclusions The results of this review suggest that PVTs which take a hierarchical approach to effort testing such as the WMT, MSVT, and NV-MSVT are preferable for use with older adults who are under investigation for possible dementia. These tests go above and beyond the traditional pass/fail approach of more traditional tests of effort because they allow the examiner to analyze the examinee’s profile of scores. The methodological limitations and challenges involved in this field of research are discussed. Dementia, Mild cognitive impairment, Malingering/symptom validity testing, Elderly/Geriatrics/Aging Introduction Cognitive testing is used in many clinical settings, alongside information gathered from other sources, to develop a comprehensive understanding of a person’s difficulties. Scores on cognitive tests are usually interpreted alongside published normative data which assume that the examinee has put forth good effort. The value and accuracy of an assessment, therefore, relies on the quality of the data to be interpreted and, as such, it is of great importance that the clinician has evaluated the examinee’s level of effort and motivation during the assessment process. Effort testing is considered a crucial component of neuropsychological evaluation according to both the British Psychological Society (BPS; McMillan et al., 2009) and the American Academy of Clinical Neuropsychology (AACN; Heilbronner et al., 2009). This has led to the creation of both purpose-built tests designed to detect non-credible effort such as the Test of Memory Malingering (TOMM; Tombaugh, 1996), the Word Memory Test (WMT; Green, 2003), and the Rey 15-Item Test (RFIT; Rey, 1964) and those which have been developed from existing neuropsychological test batteries such as the Effort Index (EI; Silverberg, Wertheimer, & Fichtenberg, 2007) and the Effort Scale (ES; Novitski, Steele, Karantzoulis, & Randolph, 2012) both derived from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS; Randolph, Tierney, Mohr, & Chase, 1998). Effort tests are also known as symptom validity tests (SVTs) or performance validity tests (PVTs); however, Larrabee (2012) distinguishes between these two terms. SVTs are self-report measures which tell the examiner whether a person’s symptomatic complaint is reflective of their true experience of symptoms whereas PVTs are cognitive tests which allow the examiner to know whether the examinee’s test performance is reflective of true cognitive ability. For the purposes of this review, the term PVT will be used alongside test of effort. There also exist published criteria which can aid clinicians in making a judgment about an examinee’s level of effort or motivation. One such set of criteria was published by Slick, Sherman, and Iverson (1999) in a landmark paper which encouraged clinicians to apply a “discrepancy method” to their judgment of poor effort (e.g., attending to inconsistencies between test scores and observed behaviors from the same domain). Slick et al. (1999) propose inspecting an examinee’s pattern of performance (e.g., comparing scores on easy and difficult items to identify inconsistent patterns of scores) alongside evidence from other sources such as the presence or absence of a substantial, external incentive and significant inconsistencies or discrepancies in the individual’s self-report. Despite these recommendations, however, it appears that effort tests are not always routinely administered as part of cognitive assessment. One study which surveyed 130 UK neuropsychologists about their practices and beliefs regarding tests of effort found that while 59% of respondents working in forensic settings said that they always used a test of effort, only 15% of respondents working in other clinical settings said the same. One-third of the respondents in this study said that there was no need to use a dedicated test of effort because non-credible symptoms were evident from the results of other tests and from the client’s general presentation during assessment (McCarter, Walton, Brooks, & Powell, 2009). Research has found, however, that clinicians’ subjective evaluation of test validity is often highly inaccurate (Faust, 1995; Faust, Hart, & Guilmette, 1988; Heaton, Smith, Lehman, & Vogt, 1978) and that analyzing performance on traditional neuropsychological measures alone is an unreliable method of detecting invalid or malingered performance (van Gorp et al., 1999). It should be noted, however, that there is a cultural divide regarding the use of effort testing as research has shown that a majority of clinicians in the United States routinely test for effort as part of neuropsychological assessment (Schroeder, Martin, & Odland, 2016). It may be that some clinicians consider effort tests to only be of relevance when there is suspicion that an individual is deliberately feigning symptoms and indeed the majority of the literature on effort testing focuses on populations in which the deliberate feigning of symptoms is thought to be most prevalent, for example medico-legal settings and disability payment assessments. Nevertheless, literature does exist which examines the validity and reliability of effort testing in various clinical groups such as brain injury (Green, Rohling, Lees-Haley, & Allen, 2001; Hampson, Kemp, Coughlan, Moulin, & Bhakta, 2014), depression (Ashendorf, Constantinou, & McCaffrey, 2004), chronic fatigue syndrome (van der Werf, Prins, Jongen, van der Meer, & Bleijenberg, 2000) and conversion and somatoform disorders (Boone & Lu, 1999). There is, however, a lack of information on how people with varying degrees of mild cognitive impairment (MCI) or dementia would be expected to perform on tests of effort as individuals with dementia are often excluded from samples used for effort test validation (Dean, Victor, Boone, Philpott, & Hess, 2009). It may be that tests of effort are not routinely validated in samples of older adults who are under investigation for memory problems because it is thought that they are unlikely to be feigning symptoms. Indeed, a study found that as few as 2% of litigants and those seeking other forms of compensation alleged dementia (Mittenberg, Patton, Canyock, & Condit, 2002). It is important, however, to approach the issue of effort from a wider definition than that of deliberate malingering. There are many reasons unrelated to financial gain that can result in non-credible effort such as: depression, medication side effects, stress, lack of interest, fatigue, lack of comprehension of the utility of the tests, or motivation to be in a “sick role” (Barker, Horner, & Bachman, 2010). When conducting cognitive assessment with older people, it is also important to consider medical and physical issues which could effect on an examinee’s performance on a test of effort such as visual impairment/disturbance, language difficulties, and chronic health conditions which can cause fatigue. In order for clinicians to be able to adequately assess the reliability of data resulting from cognitive assessment in older adults presenting with memory problems, they must know which effort tests are the most suitable for use with this population. To date, there is no systematic review which examines the literature on the use of effort testing in dementia assessment. Systematic Review Objectives This review evaluates the literature on effort testing in dementia assessment with the following objectives: review which effort tests provide the lowest rate of false-positive error in people with MCI and dementia and to examine the relationship between dementia severity and false-positive rates. Methods Search Strategy The following electronic bibliographic databases were searched: PsycINFO, Cinahl, EMBASE, Medline and Psychology and Behavioral Sciences Collection. The search did not have a start date limit. The end date was October 2017. The following search criteria were used in all databases: ([malingering OR “test* of effort” OR “symptom validity test*” OR “symptom validity” OR “effort test*” OR “validity test*” OR “performance validity” OR “non-credible effort” OR “suspect effort”] AND [dementia OR MCI OR “mild cognitive impairment” OR “geriatric*”]). Titles and abstracts of studies identified were examined to identify those pertaining to effort testing in dementia assessment. Reference lists of all included papers were also examined to identify any further relevant studies. All the titles and abstracts of identified papers featuring the use of effort testing in dementia assessment were screened against the following criteria: Inclusion criteria Studies investigating the performance of dementia and/or MCI samples on tests of effort. Exclusion criteria Studies which solely used a sample of participants asked to simulate MCI or dementia. Single case studies. Methodological Quality In order to rate the methodological quality of the studies included in this review, the studies were separated into two different categories based on their methodology. The first category pertained to papers in which a reference standard is used to establish if a diagnosis is present or absent in the participants (in this case, the diagnosis would be credible or non-credible effort) and then results on the index test (the effort test(s) of interest) are compared between the two groups. A reference standard is the best available method for establishing the presence or absence of a particular diagnosis. To rate the papers included in this first category (n = 5), a checklist was developed based on the SIGN Methodology Checklist 5 for Studies of Diagnostic Accuracy (SIGN, 2007) and the Standards for the Reporting of Diagnostic accuracy studies statement (STARD; Bossuyt et al., 2015). The quality rating checklist had a maximum score of 28 points. The second category covers the majority of the papers included in this review (n = 20) in which the researchers have recruited a sample of participants whom they consider not to meet the diagnosis (of non-credible effort). In these studies, the researchers have either excluded participants who may have motivation to feign impairment (involvement in litigation/in receipt of disability payments) or they have assumed that their sample will exert credible effort by virtue of having a diagnosis of dementia/MCI. To rate the methodological quality of these papers, the Crowe Critical Appraisal Tool (CCAT; Crowe & Sheppard, 2011) was used. The CCAT contains 54 reporting items in 8 categories and has a maximum score of 40 points. All papers were rated by the author. A second rater assessed 12/25 (48%) of the papers to examine the inter-rater reliability of the checklists. Across all the checklist items in the quality rating tools, there was 84% agreement between raters. Where discrepancies occurred, these were resolved through discussion. Outcome of Search Process A total of 25 papers met the inclusion criteria and are included in this review. Figure 1 is a flow diagram illustrating the systematic process of identifying the 25 papers included. Figure 1. View largeDownload slide Flowchart illustrating the search process. Figure 1. View largeDownload slide Flowchart illustrating the search process. Results In this review, sensitivity (also called the true positive rate) refers to the ability of the tests to identify non-credible effort when non-credible effort is present. Specificity (also called the true negative rate) refers to the ability of the tests to identify credible effort when credible effort is present. The majority of the studies included in this review involved participants who were deemed to be exerting credible effort due to not being involved in litigation or by virtue of having an established diagnosis of MCI or dementia and therefore having little to no reason to feign impairment (n = 20). This means that the methodology involved administering tests of effort to participants who were already deemed to be exerting credible effort. These studies cannot possibly investigate the sensitivity levels of the effort test(s) in question (there are no true positives present in their samples). They report specificity levels only. The studies (n = 5) which include both participants who are and are not exerting credible effort are able to report both sensitivity and specificity levels with the exception of Schroeder, Peck, Buddin, Heinrichs, and Baade (2012) who used the RBANS Effort Scale as a reference standard but who deemed all of their participants to be exerting credible effort therefore they report specificity levels only. See Tables 1–12 for data extraction which include demographic information and sensitivity and specificity levels where appropriate. This information is listed per PVT. Table 1. Data extraction table for the Test of Memory Malingering (TOMM; Tombaugh, 1996)—all results refer to a cut-off score of <45/40 on TOMM Trial two unless otherwise stated Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) TOMM sensitivitya (%) TOMM specificityb (%) Quality rating score (%) Walter et al. (2014) Dementia (mod/sev) (31) 69.48 (7.86) 15.63 (2.92) RBANS total score 60.7 (7.48) n/a 79 31/40 (78) MCI (28) 66.02 (8.02) 14.68 (2.09) 80.72 (4.47) n/a 91 Controls (30) 71.43 (8.99) 16.33 (3.19) 96.73 (8.61) n/a 100 Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 45 78 37 91 34 95 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 45 100 37 78 34 67 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) n/a 95 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) n/a 36 Dean et al. (2009) Dementia (20) Not reported Not reported MMSE 19.2 (4.4) n/a 45 30/40 (75) Merten, Bossink, & Schmand (2007) AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) n/a 70 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) n/a 100 Teichner & Wagner (2004) Dementia (21) 75.3 (6.1) 13.6 (3.3) MMSE WAIS FSIQ 19.9 (2.8) MMSE 80.6 (12) WAIS n/a 45 24 42 38 40 48 27/40 (68) MCI (36) 70.6 (8.1) 14.2 (3.2) 25.6 (2.5) MMSE 90.8 (14.8) WAIS n/a 45 91.7 42 94.4 40 97.3 Controls (21) 65.6 (8.6) 14.2 (3.6) 28.3 (1.7) MMSE 99.1 (15.3) WAIS n/a 45 100 42 100 40 100 Tombaugh (1997) Dementia (37) 69.48 (7.86) 72.1 (7.6) MMSE Not reported n/a 45 72.9 40 89.2 30/40 (75) Controls (13) 66.02 (8.02) 45.9 (15) 45 100 40 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) TOMM sensitivitya (%) TOMM specificityb (%) Quality rating score (%) Walter et al. (2014) Dementia (mod/sev) (31) 69.48 (7.86) 15.63 (2.92) RBANS total score 60.7 (7.48) n/a 79 31/40 (78) MCI (28) 66.02 (8.02) 14.68 (2.09) 80.72 (4.47) n/a 91 Controls (30) 71.43 (8.99) 16.33 (3.19) 96.73 (8.61) n/a 100 Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 45 78 37 91 34 95 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 45 100 37 78 34 67 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) n/a 95 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) n/a 36 Dean et al. (2009) Dementia (20) Not reported Not reported MMSE 19.2 (4.4) n/a 45 30/40 (75) Merten, Bossink, & Schmand (2007) AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) n/a 70 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) n/a 100 Teichner & Wagner (2004) Dementia (21) 75.3 (6.1) 13.6 (3.3) MMSE WAIS FSIQ 19.9 (2.8) MMSE 80.6 (12) WAIS n/a 45 24 42 38 40 48 27/40 (68) MCI (36) 70.6 (8.1) 14.2 (3.2) 25.6 (2.5) MMSE 90.8 (14.8) WAIS n/a 45 91.7 42 94.4 40 97.3 Controls (21) 65.6 (8.6) 14.2 (3.6) 28.3 (1.7) MMSE 99.1 (15.3) WAIS n/a 45 100 42 100 40 100 Tombaugh (1997) Dementia (37) 69.48 (7.86) 72.1 (7.6) MMSE Not reported n/a 45 72.9 40 89.2 30/40 (75) Controls (13) 66.02 (8.02) 45.9 (15) 45 100 40 100 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination; WAIS FSIQ = Wechsler Adult Intelligence Scale, Full Scale Intelligence Quotient. AD = Alzheimer’s Dementia. Table 1. Data extraction table for the Test of Memory Malingering (TOMM; Tombaugh, 1996)—all results refer to a cut-off score of <45/40 on TOMM Trial two unless otherwise stated Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) TOMM sensitivitya (%) TOMM specificityb (%) Quality rating score (%) Walter et al. (2014) Dementia (mod/sev) (31) 69.48 (7.86) 15.63 (2.92) RBANS total score 60.7 (7.48) n/a 79 31/40 (78) MCI (28) 66.02 (8.02) 14.68 (2.09) 80.72 (4.47) n/a 91 Controls (30) 71.43 (8.99) 16.33 (3.19) 96.73 (8.61) n/a 100 Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 45 78 37 91 34 95 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 45 100 37 78 34 67 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) n/a 95 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) n/a 36 Dean et al. (2009) Dementia (20) Not reported Not reported MMSE 19.2 (4.4) n/a 45 30/40 (75) Merten, Bossink, & Schmand (2007) AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) n/a 70 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) n/a 100 Teichner & Wagner (2004) Dementia (21) 75.3 (6.1) 13.6 (3.3) MMSE WAIS FSIQ 19.9 (2.8) MMSE 80.6 (12) WAIS n/a 45 24 42 38 40 48 27/40 (68) MCI (36) 70.6 (8.1) 14.2 (3.2) 25.6 (2.5) MMSE 90.8 (14.8) WAIS n/a 45 91.7 42 94.4 40 97.3 Controls (21) 65.6 (8.6) 14.2 (3.6) 28.3 (1.7) MMSE 99.1 (15.3) WAIS n/a 45 100 42 100 40 100 Tombaugh (1997) Dementia (37) 69.48 (7.86) 72.1 (7.6) MMSE Not reported n/a 45 72.9 40 89.2 30/40 (75) Controls (13) 66.02 (8.02) 45.9 (15) 45 100 40 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) TOMM sensitivitya (%) TOMM specificityb (%) Quality rating score (%) Walter et al. (2014) Dementia (mod/sev) (31) 69.48 (7.86) 15.63 (2.92) RBANS total score 60.7 (7.48) n/a 79 31/40 (78) MCI (28) 66.02 (8.02) 14.68 (2.09) 80.72 (4.47) n/a 91 Controls (30) 71.43 (8.99) 16.33 (3.19) 96.73 (8.61) n/a 100 Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 45 78 37 91 34 95 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 45 100 37 78 34 67 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) n/a 95 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) n/a 36 Dean et al. (2009) Dementia (20) Not reported Not reported MMSE 19.2 (4.4) n/a 45 30/40 (75) Merten, Bossink, & Schmand (2007) AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) n/a 70 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) n/a 100 Teichner & Wagner (2004) Dementia (21) 75.3 (6.1) 13.6 (3.3) MMSE WAIS FSIQ 19.9 (2.8) MMSE 80.6 (12) WAIS n/a 45 24 42 38 40 48 27/40 (68) MCI (36) 70.6 (8.1) 14.2 (3.2) 25.6 (2.5) MMSE 90.8 (14.8) WAIS n/a 45 91.7 42 94.4 40 97.3 Controls (21) 65.6 (8.6) 14.2 (3.6) 28.3 (1.7) MMSE 99.1 (15.3) WAIS n/a 45 100 42 100 40 100 Tombaugh (1997) Dementia (37) 69.48 (7.86) 72.1 (7.6) MMSE Not reported n/a 45 72.9 40 89.2 30/40 (75) Controls (13) 66.02 (8.02) 45.9 (15) 45 100 40 100 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination; WAIS FSIQ = Wechsler Adult Intelligence Scale, Full Scale Intelligence Quotient. AD = Alzheimer’s Dementia. Table 2. Rey 15-Item Test (RFIT; Rey, 1964)—Bortnik and colleagues (2013) use a cut-off of <9, Rudman and colleagues (2011) use a cut-off of <8 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RFIT sensitivitya (%) RFIT specificityb (%) Quality rating score (%) Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 28 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 100 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG Not reported n/a 85 28/40 (70) Dementia (mod/sev) (22) n/a 27 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RFIT sensitivitya (%) RFIT specificityb (%) Quality rating score (%) Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 28 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 100 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG Not reported n/a 85 28/40 (70) Dementia (mod/sev) (22) n/a 27 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination. Table 2. Rey 15-Item Test (RFIT; Rey, 1964)—Bortnik and colleagues (2013) use a cut-off of <9, Rudman and colleagues (2011) use a cut-off of <8 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RFIT sensitivitya (%) RFIT specificityb (%) Quality rating score (%) Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 28 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 100 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG Not reported n/a 85 28/40 (70) Dementia (mod/sev) (22) n/a 27 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RFIT sensitivitya (%) RFIT specificityb (%) Quality rating score (%) Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 28 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 100 n/a Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG Not reported n/a 85 28/40 (70) Dementia (mod/sev) (22) n/a 27 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination. Table 3. Coin in the Hand (CIH; Kapur, 1994)—all studies used a cut-off of ≤7/10 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) CIH specificitya (%) Quality rating score (CCAT) (%) Schroeder et al. (2012) Dementia (45) 77.98 (7.05) 12.76 (3.02) MMSE 21.47 (5.71) 98 31/40 (78) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 100 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 77 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) CIH specificitya (%) Quality rating score (CCAT) (%) Schroeder et al. (2012) Dementia (45) 77.98 (7.05) 12.76 (3.02) MMSE 21.47 (5.71) 98 31/40 (78) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 100 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 77 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination. Table 3. Coin in the Hand (CIH; Kapur, 1994)—all studies used a cut-off of ≤7/10 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) CIH specificitya (%) Quality rating score (CCAT) (%) Schroeder et al. (2012) Dementia (45) 77.98 (7.05) 12.76 (3.02) MMSE 21.47 (5.71) 98 31/40 (78) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 100 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 77 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) CIH specificitya (%) Quality rating score (CCAT) (%) Schroeder et al. (2012) Dementia (45) 77.98 (7.05) 12.76 (3.02) MMSE 21.47 (5.71) 98 31/40 (78) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 100 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 77 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CAMCOG = Cambridge Cognitive Examination. Table 4. Word Memory Test (WMT; Green, 2003) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) WMT specificitya (%) Quality rating score (%) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) 71 100 100 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 48 100 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) 21.6 96.7 96.7 Controls (19) 55.8 (7.5) 0 0 n/a 100 Martins & Martins (2010) MCI (21) 71.2 (2) Not reported WMS-III (Logical Memory Subtest) Not reported 67 95.2 95.2 30/40 (75) Merten et al. (2007)b AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 50b n/a 50b 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100b 0b Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) WMT specificitya (%) Quality rating score (%) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) 71 100 100 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 48 100 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) 21.6 96.7 96.7 Controls (19) 55.8 (7.5) 0 0 n/a 100 Martins & Martins (2010) MCI (21) 71.2 (2) Not reported WMS-III (Logical Memory Subtest) Not reported 67 95.2 95.2 30/40 (75) Merten et al. (2007)b AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 50b n/a 50b 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100b 0b aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). bBased on subtests passed/failed—profile analysis not used. CDR = Clinical Dementia Rating; MMSE = Mini-Mental State Examination; AD = Alzheimer’s Dementia. Table 4. Word Memory Test (WMT; Green, 2003) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) WMT specificitya (%) Quality rating score (%) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) 71 100 100 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 48 100 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) 21.6 96.7 96.7 Controls (19) 55.8 (7.5) 0 0 n/a 100 Martins & Martins (2010) MCI (21) 71.2 (2) Not reported WMS-III (Logical Memory Subtest) Not reported 67 95.2 95.2 30/40 (75) Merten et al. (2007)b AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 50b n/a 50b 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100b 0b Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) WMT specificitya (%) Quality rating score (%) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) 71 100 100 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 48 100 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) 21.6 96.7 96.7 Controls (19) 55.8 (7.5) 0 0 n/a 100 Martins & Martins (2010) MCI (21) 71.2 (2) Not reported WMS-III (Logical Memory Subtest) Not reported 67 95.2 95.2 30/40 (75) Merten et al. (2007)b AD (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 50b n/a 50b 30/40 (75) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100b 0b aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). bBased on subtests passed/failed—profile analysis not used. CDR = Clinical Dementia Rating; MMSE = Mini-Mental State Examination; AD = Alzheimer’s Dementia. Table 5. Medical Symptom Validity Test (MSVT; Green, 2004) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produce dementia profile (met Criterion A not Criterion B) MSVT sensitivitya (%) MSVT specificityb (%) Quality rating score (%) Suesse et al. (2015) Dementia (15) Not reported Not reported n/a n/a 19.7 86.7 n/a 86.7 28/40 (70) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) Not reported Not reported Not reported Not reported 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 44 100 n/a 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) Not reported Not reported n/a Not reported Controls (19) 55.8 (7.5) 0 Not reported Not reported n/a Not reported Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65b 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28b Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10) 36 (10) 17 (2) n/a 100 40 60 n/a Howe et al. (2007) Disability WAIS-III FSIQ FSIQ 35/40 (88) Dementia (5) 56.60 (4.95) 11.60 (2.30) 82.20 (5.63) 60 100 n/a 100 MCI (3) 44.33 (19.50) 13.33 (2.31) 89.33 (5.63) 66.7 0 100 n/a Controls (1) 58 13 102 0 n/a n/a n/a No Disability FSIQ Dementia early (13) 73.54 (9.03) 12 (2.42) 89.27 (14.54) 38.46 80 n/a 80 Dementia advanced (18) 76.39 (6.89) 13.83 (2.92) 86.77 (13.45) 83.33 86 n/a 86 MCI (16) 69.50 (9.60) 15.75 (2.93) 100.94 (10.34) 12.5 100 n/a 100 Controls (5) 57.20 (17.33) 15.40 (1.67) 107.80 (10.26) 0 n/a n/a n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produce dementia profile (met Criterion A not Criterion B) MSVT sensitivitya (%) MSVT specificityb (%) Quality rating score (%) Suesse et al. (2015) Dementia (15) Not reported Not reported n/a n/a 19.7 86.7 n/a 86.7 28/40 (70) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) Not reported Not reported Not reported Not reported 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 44 100 n/a 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) Not reported Not reported n/a Not reported Controls (19) 55.8 (7.5) 0 Not reported Not reported n/a Not reported Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65b 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28b Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10) 36 (10) 17 (2) n/a 100 40 60 n/a Howe et al. (2007) Disability WAIS-III FSIQ FSIQ 35/40 (88) Dementia (5) 56.60 (4.95) 11.60 (2.30) 82.20 (5.63) 60 100 n/a 100 MCI (3) 44.33 (19.50) 13.33 (2.31) 89.33 (5.63) 66.7 0 100 n/a Controls (1) 58 13 102 0 n/a n/a n/a No Disability FSIQ Dementia early (13) 73.54 (9.03) 12 (2.42) 89.27 (14.54) 38.46 80 n/a 80 Dementia advanced (18) 76.39 (6.89) 13.83 (2.92) 86.77 (13.45) 83.33 86 n/a 86 MCI (16) 69.50 (9.60) 15.75 (2.93) 100.94 (10.34) 12.5 100 n/a 100 Controls (5) 57.20 (17.33) 15.40 (1.67) 107.80 (10.26) 0 n/a n/a n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cBased on subtests passed/failed—profile analysis not used. CDR = Clinical Dementia Rating; CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination; WAIS FSIQ = Wechsler Adult Intelligence Scale, Full Scale Intelligence Quotient. Table 5. Medical Symptom Validity Test (MSVT; Green, 2004) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produce dementia profile (met Criterion A not Criterion B) MSVT sensitivitya (%) MSVT specificityb (%) Quality rating score (%) Suesse et al. (2015) Dementia (15) Not reported Not reported n/a n/a 19.7 86.7 n/a 86.7 28/40 (70) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) Not reported Not reported Not reported Not reported 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 44 100 n/a 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) Not reported Not reported n/a Not reported Controls (19) 55.8 (7.5) 0 Not reported Not reported n/a Not reported Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65b 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28b Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10) 36 (10) 17 (2) n/a 100 40 60 n/a Howe et al. (2007) Disability WAIS-III FSIQ FSIQ 35/40 (88) Dementia (5) 56.60 (4.95) 11.60 (2.30) 82.20 (5.63) 60 100 n/a 100 MCI (3) 44.33 (19.50) 13.33 (2.31) 89.33 (5.63) 66.7 0 100 n/a Controls (1) 58 13 102 0 n/a n/a n/a No Disability FSIQ Dementia early (13) 73.54 (9.03) 12 (2.42) 89.27 (14.54) 38.46 80 n/a 80 Dementia advanced (18) 76.39 (6.89) 13.83 (2.92) 86.77 (13.45) 83.33 86 n/a 86 MCI (16) 69.50 (9.60) 15.75 (2.93) 100.94 (10.34) 12.5 100 n/a 100 Controls (5) 57.20 (17.33) 15.40 (1.67) 107.80 (10.26) 0 n/a n/a n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produce dementia profile (met Criterion A not Criterion B) MSVT sensitivitya (%) MSVT specificityb (%) Quality rating score (%) Suesse et al. (2015) Dementia (15) Not reported Not reported n/a n/a 19.7 86.7 n/a 86.7 28/40 (70) Green et al. (2011) Dementia group 1 (42) 70.9 (8) Not reported CDR 1.05 (0.6) Not reported Not reported Not reported Not reported 28/40 (70) Dementia group 2 (23) 65.2 (8) 0.83 (0.35) 44 100 n/a 100 MCI (60) 68.8 (8.9) 0.5 single domain (29) 0.5 multi domain (31) Not reported Not reported n/a Not reported Controls (19) 55.8 (7.5) 0 Not reported Not reported n/a Not reported Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65b 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28b Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10) 36 (10) 17 (2) n/a 100 40 60 n/a Howe et al. (2007) Disability WAIS-III FSIQ FSIQ 35/40 (88) Dementia (5) 56.60 (4.95) 11.60 (2.30) 82.20 (5.63) 60 100 n/a 100 MCI (3) 44.33 (19.50) 13.33 (2.31) 89.33 (5.63) 66.7 0 100 n/a Controls (1) 58 13 102 0 n/a n/a n/a No Disability FSIQ Dementia early (13) 73.54 (9.03) 12 (2.42) 89.27 (14.54) 38.46 80 n/a 80 Dementia advanced (18) 76.39 (6.89) 13.83 (2.92) 86.77 (13.45) 83.33 86 n/a 86 MCI (16) 69.50 (9.60) 15.75 (2.93) 100.94 (10.34) 12.5 100 n/a 100 Controls (5) 57.20 (17.33) 15.40 (1.67) 107.80 (10.26) 0 n/a n/a n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cBased on subtests passed/failed—profile analysis not used. CDR = Clinical Dementia Rating; CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination; WAIS FSIQ = Wechsler Adult Intelligence Scale, Full Scale Intelligence Quotient. Table 6. Non-verbal Medical Symptom Validity Test (NV-MSVT; Green, 2008) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) NV-MSVT sensitivitya (%) NV-MSVT specificityb (%) Quality rating score (%) Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65c 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28c Henry et al. (2010) Dementia (21) 59.1 (16.1) 13.1 (3.4) MMSE 25.7 (3.9) 61 61 n/a 100 28/40 (70) Without dementia (n = 44) 15 15 97.7 Controls (50) 62.8 (7.1) 15.8 (3) 28.7 (1.1) 2 2 100 Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10)d 36 (10) 17 (2) n/a 90 40 60 n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) NV-MSVT sensitivitya (%) NV-MSVT specificityb (%) Quality rating score (%) Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65c 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28c Henry et al. (2010) Dementia (21) 59.1 (16.1) 13.1 (3.4) MMSE 25.7 (3.9) 61 61 n/a 100 28/40 (70) Without dementia (n = 44) 15 15 97.7 Controls (50) 62.8 (7.1) 15.8 (3) 28.7 (1.1) 2 2 100 Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10)d 36 (10) 17 (2) n/a 90 40 60 n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cBased on subtests passed/failed – profile analysis not used. dAsked to simulate memory impairment. CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination. Table 6. Non-verbal Medical Symptom Validity Test (NV-MSVT; Green, 2008) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) NV-MSVT sensitivitya (%) NV-MSVT specificityb (%) Quality rating score (%) Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65c 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28c Henry et al. (2010) Dementia (21) 59.1 (16.1) 13.1 (3.4) MMSE 25.7 (3.9) 61 61 n/a 100 28/40 (70) Without dementia (n = 44) 15 15 97.7 Controls (50) 62.8 (7.1) 15.8 (3) 28.7 (1.1) 2 2 100 Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10)d 36 (10) 17 (2) n/a 90 40 60 n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) % Failed easy subtests (met Criterion A) % Produced dementia profile (met Criterion A not Criterion B) NV-MSVT sensitivitya (%) NV-MSVT specificityb (%) Quality rating score (%) Rudman et al. (2011)c Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 35 Not analyzed n/a 65c 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 72 n/a 28c Henry et al. (2010) Dementia (21) 59.1 (16.1) 13.1 (3.4) MMSE 25.7 (3.9) 61 61 n/a 100 28/40 (70) Without dementia (n = 44) 15 15 97.7 Controls (50) 62.8 (7.1) 15.8 (3) 28.7 (1.1) 2 2 100 Singhal et al. (2009) Dementia (10) 81.7 (4.6) 10 (2.9) MMSE 15.5 (5.3) 100 100 n/a 100 31/40 (78) Simulators (10)d 36 (10) 17 (2) n/a 90 40 60 n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cBased on subtests passed/failed – profile analysis not used. dAsked to simulate memory impairment. CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination. Table 7. Amsterdam Short-Term Memory Test (ASTM; Schagen et al., 1997)—results based on cut-off of 84/85 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) ASTM specificitya (%) Quality rating score (CCAT) (%) Merten et al. (2007) AD dementia (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 10 30/40 (75%) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) ASTM specificitya (%) Quality rating score (CCAT) (%) Merten et al. (2007) AD dementia (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 10 30/40 (75%) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination. Table 7. Amsterdam Short-Term Memory Test (ASTM; Schagen et al., 1997)—results based on cut-off of 84/85 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) ASTM specificitya (%) Quality rating score (CCAT) (%) Merten et al. (2007) AD dementia (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 10 30/40 (75%) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) ASTM specificitya (%) Quality rating score (CCAT) (%) Merten et al. (2007) AD dementia (20) 73.5 (4.8) 11.7 (3.3) MMSE 22.2 (2.9) 10 30/40 (75%) Controls (14) 76.6 (6.7) 11.3 (3.7) 28.9 (1.0) 100 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination. Table 8. Dot Counting Test (DCT; Rey, 1941) Rudman et al. (2011) results based on “total ungrouped time< total group time”. Dean et al. (2009) and Boone et al. (2002) results based on “mean ungrouped dots counting time + error grouped dot counting time + errors” ≤17 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) DCT specificitya (%) Quality rating score (CCAT) (%) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 90 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 68 Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) 50 30/40 (75) Boone et al. (2002) Dementia (mild) (16) 75.4 (9.3) 12.7 (2.6) MMSE >20 75 21/40 (53) Dementia (mod) 78.1 (10.4) 13 (2.4) 10–20 33.4 Controls 63.5 (8.8) 15.3 (2.4) n/a 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) DCT specificitya (%) Quality rating score (CCAT) (%) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 90 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 68 Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) 50 30/40 (75) Boone et al. (2002) Dementia (mild) (16) 75.4 (9.3) 12.7 (2.6) MMSE >20 75 21/40 (53) Dementia (mod) 78.1 (10.4) 13 (2.4) 10–20 33.4 Controls 63.5 (8.8) 15.3 (2.4) n/a 100 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination. Table 8. Dot Counting Test (DCT; Rey, 1941) Rudman et al. (2011) results based on “total ungrouped time< total group time”. Dean et al. (2009) and Boone et al. (2002) results based on “mean ungrouped dots counting time + error grouped dot counting time + errors” ≤17 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) DCT specificitya (%) Quality rating score (CCAT) (%) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 90 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 68 Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) 50 30/40 (75) Boone et al. (2002) Dementia (mild) (16) 75.4 (9.3) 12.7 (2.6) MMSE >20 75 21/40 (53) Dementia (mod) 78.1 (10.4) 13 (2.4) 10–20 33.4 Controls 63.5 (8.8) 15.3 (2.4) n/a 100 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) DCT specificitya (%) Quality rating score (CCAT) (%) Rudman et al. (2011) Dementia (mild) (20) 58.3 Not reported CAMCOG 88.60 (5.03) 90 28/40 (70) Dementia (mod/sev) (22) 62.45 (16.21) 68 Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) 50 30/40 (75) Boone et al. (2002) Dementia (mild) (16) 75.4 (9.3) 12.7 (2.6) MMSE >20 75 21/40 (53) Dementia (mod) 78.1 (10.4) 13 (2.4) 10–20 33.4 Controls 63.5 (8.8) 15.3 (2.4) n/a 100 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). CAMCOG = Cambridge Cognitive Examination; MMSE = Mini-Mental State Examination. Table 9. Finger Tapping Test (FTT; Reitan & Wolfson, 1985) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) FTT specificitya (%) Quality rating score (CCAT) (%) Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) Women Dom ≤28 69 Men Dom≤35 69 30/40 (75) Arnold et al. (2005) Dementia (31) 67.48 (10.95) 13.61 (3.87) Not reported n/a Women Dom ≤28 75 Non-dom ≤25 87 Sum ≤58 80 Difference ≤5 87 Men Dom ≤35 87 Non-dom ≤30 80 Sum ≤66 71 Difference ≤−2 100 25/40 (63) Controls (18) 66.67 (6.51) 17.89 (2.06) Women Dom ≤28 100 Non-dom ≤25 87 Sum ≤58 100 Difference ≤5 100 Men Dom ≤35 100 Non-dom ≤30 100 Sum ≤66 100 Difference ≤−2 90 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) FTT specificitya (%) Quality rating score (CCAT) (%) Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) Women Dom ≤28 69 Men Dom≤35 69 30/40 (75) Arnold et al. (2005) Dementia (31) 67.48 (10.95) 13.61 (3.87) Not reported n/a Women Dom ≤28 75 Non-dom ≤25 87 Sum ≤58 80 Difference ≤5 87 Men Dom ≤35 87 Non-dom ≤30 80 Sum ≤66 71 Difference ≤−2 100 25/40 (63) Controls (18) 66.67 (6.51) 17.89 (2.06) Women Dom ≤28 100 Non-dom ≤25 87 Sum ≤58 100 Difference ≤5 100 Men Dom ≤35 100 Non-dom ≤30 100 Sum ≤66 100 Difference ≤−2 90 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination. Table 9. Finger Tapping Test (FTT; Reitan & Wolfson, 1985) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) FTT specificitya (%) Quality rating score (CCAT) (%) Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) Women Dom ≤28 69 Men Dom≤35 69 30/40 (75) Arnold et al. (2005) Dementia (31) 67.48 (10.95) 13.61 (3.87) Not reported n/a Women Dom ≤28 75 Non-dom ≤25 87 Sum ≤58 80 Difference ≤5 87 Men Dom ≤35 87 Non-dom ≤30 80 Sum ≤66 71 Difference ≤−2 100 25/40 (63) Controls (18) 66.67 (6.51) 17.89 (2.06) Women Dom ≤28 100 Non-dom ≤25 87 Sum ≤58 100 Difference ≤5 100 Men Dom ≤35 100 Non-dom ≤30 100 Sum ≤66 100 Difference ≤−2 90 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) FTT specificitya (%) Quality rating score (CCAT) (%) Dean et al. (2009) Dementia (80) Not reported Not reported MMSE 18.8 (5) Women Dom ≤28 69 Men Dom≤35 69 30/40 (75) Arnold et al. (2005) Dementia (31) 67.48 (10.95) 13.61 (3.87) Not reported n/a Women Dom ≤28 75 Non-dom ≤25 87 Sum ≤58 80 Difference ≤5 87 Men Dom ≤35 87 Non-dom ≤30 80 Sum ≤66 71 Difference ≤−2 100 25/40 (63) Controls (18) 66.67 (6.51) 17.89 (2.06) Women Dom ≤28 100 Non-dom ≤25 87 Sum ≤58 100 Difference ≤5 100 Men Dom ≤35 100 Non-dom ≤30 100 Sum ≤66 100 Difference ≤−2 90 aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination. Table 10. RBANS Effort Index (EI; Silverberg et al., 2007)—all results refer to a cut-off of >3 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort Index Sensitivitya (%) Effort Index Specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 63 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 93 n/a Burton et al. (2015) AD (90) Not reported Not reported CDR Not reported n/a 51 27/40 (68) Non-AD dementia (55) n/a 54 Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 41 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 89 n/a Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 69.6 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 50 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.608) 21/40 (53) Probable AD (54) n/a Not reported Controls (540) n/a Not reported Duff et al. (2011) AD (126) 76.7 (6.8) <9 years = 12 9–11 years = 14 12 years = 38 13–15 years = 10 >15 years = 26 RBANS total scores 65.9 (5.9) n/a 67.1 31/40 (78) aMCI (72) 72 (82.1) <9 years = 0 9–11 years = 3 12 years = 17 13–15 years = 23 >15 years = 57 92.3 (9.1) n/a 100 Controls (796) 73.4 (5.9) <9 years = 5 9–11 years = 11 12 years = 26 13–15 years = 30 >15 years = 28 95.7 (13.3) n/a 97.1 Barker et al. (2010) Suspect effort (45) 67.1 (10.3) 12 (3) RBANS total index scores IM 57 (16.4) DM 51.6 (14.7) A 60.7 (15.6) L 72 (20.6) VS 70.7 (20.9) n/a 42.2 22/28 (79) Good effort (258) 72.5 (8.8) 12.5 (3.5) IM 75.1 (15.8) DM 76 (19.9) A 81.9 (16.1) L 88.3 (10.6) VS 84.3 (17.7) 95.3 n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort Index Sensitivitya (%) Effort Index Specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 63 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 93 n/a Burton et al. (2015) AD (90) Not reported Not reported CDR Not reported n/a 51 27/40 (68) Non-AD dementia (55) n/a 54 Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 41 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 89 n/a Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 69.6 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 50 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.608) 21/40 (53) Probable AD (54) n/a Not reported Controls (540) n/a Not reported Duff et al. (2011) AD (126) 76.7 (6.8) <9 years = 12 9–11 years = 14 12 years = 38 13–15 years = 10 >15 years = 26 RBANS total scores 65.9 (5.9) n/a 67.1 31/40 (78) aMCI (72) 72 (82.1) <9 years = 0 9–11 years = 3 12 years = 17 13–15 years = 23 >15 years = 57 92.3 (9.1) n/a 100 Controls (796) 73.4 (5.9) <9 years = 5 9–11 years = 11 12 years = 26 13–15 years = 30 >15 years = 28 95.7 (13.3) n/a 97.1 Barker et al. (2010) Suspect effort (45) 67.1 (10.3) 12 (3) RBANS total index scores IM 57 (16.4) DM 51.6 (14.7) A 60.7 (15.6) L 72 (20.6) VS 70.7 (20.9) n/a 42.2 22/28 (79) Good effort (258) 72.5 (8.8) 12.5 (3.5) IM 75.1 (15.8) DM 76 (19.9) A 81.9 (16.1) L 88.3 (10.6) VS 84.3 (17.7) 95.3 n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cAsked to simulate memory impairment. MMSE = Mini-Mental State Examination; RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; CDR = Clinical Dementia Rating aMCI = amnestic; MCI AD = Alzheimer’s Dementia; IM = Immediate Memory; DM = Delayed Memory; A = Attention; L = Language; VS = Visuospatial. Table 10. RBANS Effort Index (EI; Silverberg et al., 2007)—all results refer to a cut-off of >3 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort Index Sensitivitya (%) Effort Index Specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 63 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 93 n/a Burton et al. (2015) AD (90) Not reported Not reported CDR Not reported n/a 51 27/40 (68) Non-AD dementia (55) n/a 54 Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 41 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 89 n/a Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 69.6 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 50 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.608) 21/40 (53) Probable AD (54) n/a Not reported Controls (540) n/a Not reported Duff et al. (2011) AD (126) 76.7 (6.8) <9 years = 12 9–11 years = 14 12 years = 38 13–15 years = 10 >15 years = 26 RBANS total scores 65.9 (5.9) n/a 67.1 31/40 (78) aMCI (72) 72 (82.1) <9 years = 0 9–11 years = 3 12 years = 17 13–15 years = 23 >15 years = 57 92.3 (9.1) n/a 100 Controls (796) 73.4 (5.9) <9 years = 5 9–11 years = 11 12 years = 26 13–15 years = 30 >15 years = 28 95.7 (13.3) n/a 97.1 Barker et al. (2010) Suspect effort (45) 67.1 (10.3) 12 (3) RBANS total index scores IM 57 (16.4) DM 51.6 (14.7) A 60.7 (15.6) L 72 (20.6) VS 70.7 (20.9) n/a 42.2 22/28 (79) Good effort (258) 72.5 (8.8) 12.5 (3.5) IM 75.1 (15.8) DM 76 (19.9) A 81.9 (16.1) L 88.3 (10.6) VS 84.3 (17.7) 95.3 n/a Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort Index Sensitivitya (%) Effort Index Specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 63 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 93 n/a Burton et al. (2015) AD (90) Not reported Not reported CDR Not reported n/a 51 27/40 (68) Non-AD dementia (55) n/a 54 Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 41 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 89 n/a Bortnik et al. (2013) Good effort (119) 77 (7) 11.42 (4) MMSE 20.8 (5) n/a 69.6 20/28 (71) Suspect effort (9) 72 (8.13) 10.44 (2.3) 17.9 (4.5) 50 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.608) 21/40 (53) Probable AD (54) n/a Not reported Controls (540) n/a Not reported Duff et al. (2011) AD (126) 76.7 (6.8) <9 years = 12 9–11 years = 14 12 years = 38 13–15 years = 10 >15 years = 26 RBANS total scores 65.9 (5.9) n/a 67.1 31/40 (78) aMCI (72) 72 (82.1) <9 years = 0 9–11 years = 3 12 years = 17 13–15 years = 23 >15 years = 57 92.3 (9.1) n/a 100 Controls (796) 73.4 (5.9) <9 years = 5 9–11 years = 11 12 years = 26 13–15 years = 30 >15 years = 28 95.7 (13.3) n/a 97.1 Barker et al. (2010) Suspect effort (45) 67.1 (10.3) 12 (3) RBANS total index scores IM 57 (16.4) DM 51.6 (14.7) A 60.7 (15.6) L 72 (20.6) VS 70.7 (20.9) n/a 42.2 22/28 (79) Good effort (258) 72.5 (8.8) 12.5 (3.5) IM 75.1 (15.8) DM 76 (19.9) A 81.9 (16.1) L 88.3 (10.6) VS 84.3 (17.7) 95.3 n/a aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). cAsked to simulate memory impairment. MMSE = Mini-Mental State Examination; RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; CDR = Clinical Dementia Rating aMCI = amnestic; MCI AD = Alzheimer’s Dementia; IM = Immediate Memory; DM = Delayed Memory; A = Attention; L = Language; VS = Visuospatial. Table 11. RBANS Effort Scale (ES; Novitski, Steele, Karantzoulis & Randolph)—all results refer to a cut-off of <12 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort scale sensitivitya (%) Effort scale specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 42 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 71 n/a Burton et al. (2015) AD dementia (53) Not reported Not reported CDR Not reported n/a 96 69 27/40 (68) Non-AD dementia (36) n/a Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 81 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 88 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.908) 21/40 (53) probable AD (54) Not reported Controls (540) 84.9 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort scale sensitivitya (%) Effort scale specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 42 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 71 n/a Burton et al. (2015) AD dementia (53) Not reported Not reported CDR Not reported n/a 96 69 27/40 (68) Non-AD dementia (36) n/a Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 81 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 88 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.908) 21/40 (53) probable AD (54) Not reported Controls (540) 84.9 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). RBANS = Repeatable Battery for the Assessment of Neuropsychological Status. bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CDR = Clinical Dementia Rating. cAsked to simulate memory impairment. AD = Alzheimer’s Dementia. Table 11. RBANS Effort Scale (ES; Novitski, Steele, Karantzoulis & Randolph)—all results refer to a cut-off of <12 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort scale sensitivitya (%) Effort scale specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 42 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 71 n/a Burton et al. (2015) AD dementia (53) Not reported Not reported CDR Not reported n/a 96 69 27/40 (68) Non-AD dementia (36) n/a Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 81 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 88 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.908) 21/40 (53) probable AD (54) Not reported Controls (540) 84.9 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) Effort scale sensitivitya (%) Effort scale specificityb (%) Quality rating score (%) Paulson et al. (2015) Good effort (189) 69.2 (9.4) 12.9 (3.2) MMSE RBANS Total scores 27.5 (2.2) MMSE 85 (12.2) RBANS n/a 42 27/28 (96) Suspect effort (45) 64.2 (10.9) 12.3 (2.9) 23.1 (4.9) MMSE 59.9 (10.7) RBANS 71 n/a Burton et al. (2015) AD dementia (53) Not reported Not reported CDR Not reported n/a 96 69 27/40 (68) Non-AD dementia (36) n/a Dunham et al. (2014) Dementia (46) 76.44 (10.49) 11.17 (2.82) RBANS Total scores 57.48 (11.70) n/a 81 20/28 (71) Simulators (44)c 27.82 (9.01) 16.41 (0.82) 48.52 (8.66) 88 n/a Novitski et al. (2012) aMCI (15) 80.61 (6.33) Not reported RBANS total scores 64.58 (12.89) n/a Not reported (AUC 0.908) 21/40 (53) probable AD (54) Not reported Controls (540) 84.9 aSensitivity means that the test correctly identified non-credible effort (i.e., the proportion of true positives). RBANS = Repeatable Battery for the Assessment of Neuropsychological Status. bSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; CDR = Clinical Dementia Rating. cAsked to simulate memory impairment. AD = Alzheimer’s Dementia. Table 12. Reliable Digit Span (RDS; Greiffenstein et al., 1994)—all results refer to a cut-off of ≤6 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RDS specificitya (%) Quality rating score (CCAT) (%) Zenisek et al. (2016) AD (133) 72.6 (7.8) 14.8 (2.9) MoCA 21 (4.8) 80.5 23/40 (58) VAD (8) 75 DLB (27) 85.2 FTD (15) 73.3 MCI (168) 94.6 Loring et al. (2016) AD (178) 75.7 (7.5) Not reported MMSE 23.3 (2) 87 31/40 (78) aMCI (365) 74.9 (7.2) 27 (1.8) 96 Controls (206) 76 (5) 29.1 (1) 97 Kiewel et al. (2012) Dementia (mild) 74.6 (8.8) 14.5 (2.7) MMSE 23.4 (3.1) 89 30/40 (75) Dementia (mod) 76.5 (9.4) 14.2 (2.7) 16.8 (2.9) 76 Dementia (sev) 71.2 (10.6) 13.5 (2.7) 7.7 (3.4) 17 Dean et al. (2009) Dementia (172) Not reported Not reported MMSE 19.2 (4.4) 70 30/40 (75) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RDS specificitya (%) Quality rating score (CCAT) (%) Zenisek et al. (2016) AD (133) 72.6 (7.8) 14.8 (2.9) MoCA 21 (4.8) 80.5 23/40 (58) VAD (8) 75 DLB (27) 85.2 FTD (15) 73.3 MCI (168) 94.6 Loring et al. (2016) AD (178) 75.7 (7.5) Not reported MMSE 23.3 (2) 87 31/40 (78) aMCI (365) 74.9 (7.2) 27 (1.8) 96 Controls (206) 76 (5) 29.1 (1) 97 Kiewel et al. (2012) Dementia (mild) 74.6 (8.8) 14.5 (2.7) MMSE 23.4 (3.1) 89 30/40 (75) Dementia (mod) 76.5 (9.4) 14.2 (2.7) 16.8 (2.9) 76 Dementia (sev) 71.2 (10.6) 13.5 (2.7) 7.7 (3.4) 17 Dean et al. (2009) Dementia (172) Not reported Not reported MMSE 19.2 (4.4) 70 30/40 (75) aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; aMCI = amnestic MCI AD = Alzheimer’s Dementia; VAD = Vascular Dementia; DLB = Dementia with Lewy Bodies; FTD = Frontotemporal Dementia. Table 12. Reliable Digit Span (RDS; Greiffenstein et al., 1994)—all results refer to a cut-off of ≤6 Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RDS specificitya (%) Quality rating score (CCAT) (%) Zenisek et al. (2016) AD (133) 72.6 (7.8) 14.8 (2.9) MoCA 21 (4.8) 80.5 23/40 (58) VAD (8) 75 DLB (27) 85.2 FTD (15) 73.3 MCI (168) 94.6 Loring et al. (2016) AD (178) 75.7 (7.5) Not reported MMSE 23.3 (2) 87 31/40 (78) aMCI (365) 74.9 (7.2) 27 (1.8) 96 Controls (206) 76 (5) 29.1 (1) 97 Kiewel et al. (2012) Dementia (mild) 74.6 (8.8) 14.5 (2.7) MMSE 23.4 (3.1) 89 30/40 (75) Dementia (mod) 76.5 (9.4) 14.2 (2.7) 16.8 (2.9) 76 Dementia (sev) 71.2 (10.6) 13.5 (2.7) 7.7 (3.4) 17 Dean et al. (2009) Dementia (172) Not reported Not reported MMSE 19.2 (4.4) 70 30/40 (75) Study Sample (n) Mean age (SD) Mean education (SD) Impairment measure Mean score on impairment measure (SD) RDS specificitya (%) Quality rating score (CCAT) (%) Zenisek et al. (2016) AD (133) 72.6 (7.8) 14.8 (2.9) MoCA 21 (4.8) 80.5 23/40 (58) VAD (8) 75 DLB (27) 85.2 FTD (15) 73.3 MCI (168) 94.6 Loring et al. (2016) AD (178) 75.7 (7.5) Not reported MMSE 23.3 (2) 87 31/40 (78) aMCI (365) 74.9 (7.2) 27 (1.8) 96 Controls (206) 76 (5) 29.1 (1) 97 Kiewel et al. (2012) Dementia (mild) 74.6 (8.8) 14.5 (2.7) MMSE 23.4 (3.1) 89 30/40 (75) Dementia (mod) 76.5 (9.4) 14.2 (2.7) 16.8 (2.9) 76 Dementia (sev) 71.2 (10.6) 13.5 (2.7) 7.7 (3.4) 17 Dean et al. (2009) Dementia (172) Not reported Not reported MMSE 19.2 (4.4) 70 30/40 (75) aSpecificity means that the test correctly identified credible effort (i.e., the proportion of true negatives). MMSE = Mini-Mental State Examination; aMCI = amnestic MCI AD = Alzheimer’s Dementia; VAD = Vascular Dementia; DLB = Dementia with Lewy Bodies; FTD = Frontotemporal Dementia. The majority of the studies included in this review therefore report specificity levels but not sensitivity levels. The results of the studies included in this review will be reported by effort test and grouped by purpose-built versus embedded effort tests: Purpose-Built PVTs Test of Memory Malingering (TOMM; Tombaugh, 1996). Rey 15-Item Test (RFIT; Rey, 1964). The Coin in the Hand (CIH; Kapur, 1994). Word Memory Test (WMT; Green, 2003). Medical Symptom Validity Test (MSVT; Green, 2004). Non-Verbal Symptom Validity Test (NV-MSVT; Green, 2008). Amsterdam Short Memory Test (ASTM; Schagen, Schmand, de Sterke &, Lindeboom, 1997). Dot Counting Test (DCT; Rey, 1941). Finger Tapping Test (FTT; Reitan & Wolfson, 1985). Embedded PVTs Repeatable Battery for the Assessment of Neurological Status (RBANS; Randolph et al., 1998) Effort Index (EI; Silverberg et al., 2007). Effort Scale (ES; Novitski et al., 2012). Two novel indices (PVI and CRIER) (Paulson, Horner, & Bachman, 2015). Reliable Digit Span (RDS; Greiffenstein, Baker, & Gola, 1994). Note that the study by Dean and colleagues (2009) included in this review investigated a total of 18 stand-alone and embedded effort tests. It was out with the scope of this review to include all of these PVTs however those which have also been investigated by other studies have been included. These are TOMM, RFIT, DCT and RDS. Purpose-Built PVTs Test of Memory Malingering (TOMM; Tombaugh, 1996) Seven of the 25 papers included in this review investigated the use of the TOMM, one of the most widely used PVTs. The results of the studies can be found in Table 1. The TOMM is a picture-recognition, forced-choice, purpose-designed effort test consisting of two learning trials and an optional retention trial. A cut-off of <45 for Trial 2 suggests that a score lower than this is indicative of poor effort. Across the seven studies, pass rates for the dementia groups (Trial 2 <45) ranged from a low of 24% (Teichner & Wagner, 2004) to a high of 95% (Rudman, Oyebode, Jones, & Bentham, 2011). Only two of the seven studies investigated the utility of the TOMM in MCI samples (Teichner & Wagner, 2004; Walter, Morris, SwierVosnos, & Pliskin, 2014). Both studies found similar pass rates for these samples (91.7% and 90.3%, respectively). Drawing comparisons between the results of these studies is compromised to an extent, because they use different criteria for diagnosing dementia (DSM-III, DSM-IV, and the ADRDA-NINDS) and they also assess cognitive function using different tools (five report MMSE scores, one uses the RBANS and one the CAMCOG). This is important because one reason for the discrepancy in results across studies might be that the samples include individuals with significantly different levels of cognitive function. The difference in results reported by Tombaugh (1997) and Teichner and Wagner (2004) may be explained by dementia severity. Tombaugh states that 4/37 dementia participants (i.e., 10% of their dementia sample) who scored below 40 on the TOMM, had MMSE scores of 7, 15, 16, and 19. The paper does not, however, give any detail about the MMSE scores of the rest of the sample (presumably the remaining participants all of whom scored >45 in this sample had MMSE scores of >19). In Teichner and Wagner’s (2004) sample, however, 9/21 (i.e., 42.9% of their dementia sample), had MMSE scores lower than 19. It may therefore be that Teichner and Wagner’s (2004) sample was more cognitively impaired than that of Tombaugh’s (1997). Rudman, and colleagues (2011) found a specificity of 95% for the TOMM, however this was in a sample of mildly impaired dementia participants. Specificity dropped to 36% in their moderate to severely impaired sample. Bortnik, Horner, and Bachman (2013), Teichner and Wagner (2004), and Tombaugh (1997) all give data for alternative cut-offs. A cut-off of 40 produced a specificity of 89.2% in Tombaugh’s sample however the same cut-off yielded only 48% specificity in Teichner and Wagner’s dementia sample (cf. 97.3% of their MCI group). In the Bortnik et al. (2013) good effort dementia sample, the TOMM reached 95% specificity when the cut-off was lowered to 34 There are also some flaws in the reporting of results across studies. Tombaugh (1997), who received a score of 30/40 on the CCAT, states that ‘a cutting score of 45 on Trial 2 produced a high level of specificity. It correctly classified 95% of all non-demented patients (91% of all patients) as non-malingering’ (p. 265). As previously mentioned however, 89.1% of Tombaugh’s (1997) dementia sample passed the TOMM but only when a cut-off score of <40 was used. This drops to 72.9% with the recommended cut-off of <45, meaning that approximately one in four of their dementia patients were incorrectly classified as putting forth non-credible effort. Additionally, with the exception of Bortnik and colleagues (2013), sample sizes across studies were small. Rey 15-Item Test (RFIT; Rey, 1964) Alongside the TOMM, the RFIT is one of the most widely used effort tests in clinical practice (Slick, Tan, Strauss, & Hultsch, 2004). The task consists of studying a card for 10 s which has five rows of three characters. The test consists of a free-recall and an optional recognition trial. A score lower than 9 on the free-recall trial and a score lower than 20 on the combination equation are said to be indicative of non-credible effort (Boone, Salazar, Lu, Warner-Chacon, & Razani, 2002). The results of studies investigating the RFIT can be found in Table 2. Bortnik and colleagues (2013) reported a high sensitivity to non-credible effort in their “suspect effort” group (100%) but a very low specificity (28%) in their good effort group. Rudman and colleagues (2011) found a similar specificity level (27%) for their moderate/severe dementia group. The studies use different tools to assess cognitive impairment (MMSE and CAMCOG) however research suggests these screens are highly correlated (Heinik, Solomesh, & Berkman, 2004); therefore, it was possible to note that both Rudman and Bortnik’s dementia samples were equally impaired (mean CAMCOG 62.45, mean MMSE 20.8). Rudman found far better specificity in their mildly impaired sample (85% specificity, mean MMSE 20.8). Both studies performed similarly on the quality rating checklists (70%). The Coin in the Hand (CIH; Kapur, 1994) The Coin in the Hand Test (CIH) was developed to be a “simple, brief test designed to detect the presence of malingering in patients who are suspected of simulating poor memory performance” (Kapur, 1994, p. 385). It is a stand-alone, forced-choice test in which the clinician holds a coin in their right or left hand in front of the examinee who then closes their eyes and counts backwards from 10 before opening their eyes to report which hand the coin is in. A score of 7 or less out of 10 trials is used as the cut-off for this test. See Table 3 for the results of studies investigating the CIH. Two of the papers included in this review examined the utility of the CIH. Schroeder and colleagues (2012) used a sample of 45 inpatients with a diagnosis of dementia. The Schroeder study performed fairly well on the CCAT (31/40). In order to ensure that their sample would put forth adequate effort on the CIH, Schroeder excluded participants involved in litigation or who were collecting disability payments and they also excluded any participant failing the RBANS Effort Scale. Using a cut-off score of ≤7 resulted in a specificity of 98% in the Schroeder sample. Using the same cut-off, Rudman et al. (2011) found specificity of 100% in their mild dementia sample compared to 77% in the moderate/severe sample. Specificity therefore is high with a CIH cut-off of ≤7 as long as the examinee is not too cognitively impaired. Word Memory Test (WMT; Green, 2003) The WMT, MSVT, and NV-MSVT, all devised by Green, are PVTs which are a departure from the traditional pass/fail effort tests in that they use profile analysis to determine an individual’s level of effort. They are based on a hierarchical approach in line with the criteria devised by Slick et al. (1999). On these PVTs, a participant’s score is first compared against a cut-off (a pass/fail approach) and then for those participants who fail, their profile of scores over several subtests is analyzed. These tests are unique in that they allow the examiner to distinguish between failure due to poor effort and failure due to cognitive impairment. Green states that on the WMT, MSVT, and NV-MSVT, people with genuine cognitive impairment produce a specific profile of results, different from the pattern of results produced by those exerting non-credible effort. To differentiate between the two, the difference between the mean scores on the easy and hard subtests is calculated. Individuals with a diagnosis of dementia invariably show easy-hard differences of at least 20 points on these subtests, whereas such significant differences are rarely present in people asked to feign impairment. This pattern of results is known as the “dementia profile.” These three effort tests are described and the literature evaluated in turn. The WMT is a word-list learning task that involves learning a list of 20 word pairs which are presented twice, either on a computer screen or spoken aloud by the examiner (as in the original oral version of the test). It contains multiple subtests of which the first two are specifically designed to measure effort (Immediate and Delayed Recognition), the remaining subtests are conventional memory subtests. As stated earlier, the profile of scores on the WMT subtests (particularly the difference between the effort subtests and the conventional memory subtests) can indicate whether individuals fail the test due to insufficient effort or to the severity of their cognitive impairment. The results of the studies investigating the WMT can be found in Table 4. Merten and colleagues (2007) found that while all their controls passed the WMT effort subtests, almost all of the AD participants failed it (90% failed both the Immediate and Delayed Recognition trials). It is important to note however, that the authors were not able to analyze the profile of scores on the two effort subtests against those of the conventional memory tests because normative data for a Dutch population were not available at the time of the study. This is a significant limitation of the Merten et al. (2007) study because the researchers were only able to look at whether participants passed or failed the effort subtests and were not able to look at the profile of their scores to investigate whether they indicated a “dementia profile”. Green, Montijo, and Brockhaus (2011) found that 41/65 (63%) of their dementia sample and 13/60 (21.6%) of their MCI sample failed the easy subtests of the WMT. Using profile analysis, however, they found that every participant with dementia exhibited a “dementia profile” meaning there were no false positives. Regarding the MCI sample, only 2 of the 11 participants who failed the easy subtests of the WMT, indicated a profile suggestive of poor effort, which represents a false-positive rate of 3.3% for the total sample. The study however scored 28/40 on the CCAT due to inadequate reporting such as missing demographic data. It should perhaps also be noted that the participants were not screened for potential financial incentives, meaning that it cannot be concluded that the two participants who generated a poor effort profile were real false-positives. Martins and Martins (2010) found that 67% of their MCI sample failed the easy subtests of the WMT however 95% produced a dementia profile therefore were not misclassified as exerting non-credible effort. Medical Symptom Validity Test (MSVT; Green, 2004) The MSVT is a shorter, modified and easier version of the WMT. Five of the papers in this review examined the utility of the MSVT in people with dementia, MCI, cognitively intact controls and volunteers asked to simulate dementia and the results of these studies can be found in Table 5. Two of the papers were able to report sensitivity levels of 60% (simulators) and 100% (suspect effort MCI sample). Performance on the easy subtests was variable across the studies from only 12.5% of Howe, Anderson, Kaufman, Sachs, and Loring (2007) MCI sample failing the subtests compared to 100% of Singhals’ simulator sample. More importantly however is that by using profile analysis, specificity levels for the MSVT across the four studies ranged from 80% to 100%, meaning that very few individuals were misclassified as exhibiting poor effort. The exception was Rudman et al. (2011) who solely calculated effort based on whether participants had passed or failed the easy subtests. They did not use profile analysis. Although these results are promising, they should be treated as preliminary as the studies involved very small sample sizes. Non-Verbal Medical Symptom Validity Test (NV-MSVT; Green, 2008) The NV-MSVT is the non-verbal equivalent of the MSVT. Three studies were found to investigate the diagnostic accuracy of this PVT in dementia and healthy controls and the results of these can be found in Table 6. As noted with the MSVT, Rudman et al. (2011) found low specificity of the NV-MSVT (33% in their overall dementia sample), however they did not use profile analysis therefore their results are not complete or accurate. Henry, Merten, Wolf, and Harth (2010) found specificity of 100% in their controls and dementia sample and 97.7% in their non-dementia (neurological) sample whilst Singhal and colleagues (2009) found 100% specificity for their institutionalized dementia patients. Interestingly, Singhal’s entire dementia sample failed the effort subtests of the NV-MSVT; however, they all showed a “dementia profile”; therefore, they were not misclassified as malingering. They were also a particularly impaired sample (average MMSE of 15.5). Amsterdam Short Memory Test (ASTM; Schagen et al., 1997) The ASTM is a forced-choice test in which five examples from a category (e.g. animals, colors etc.) are read aloud by the examinee. A relatively simple mathematical problem is then presented to the examinee after which time another five words from the same category are presented. The examinee’s task is to recognize which three words are identical to those in the first list. The test maximum score is 90 and the cut-off is 84/85. Merten et al. (2007) found that all of their controls passed the ASTM however only 10% of their Alzheimer’s dementia participants passed the test (i.e., specificity, 10%) (see Table 7). Given that 70% of the same AD sample passed the TOMM, it would appear that the ASTM is unlikely to be an appropriate choice of PVT for individuals with cognitive impairment due to a possible dementia because the false-positive rate is likely to be high. Dot Counting Test (DCT; Rey, 1941) The DCT is a task in which the examinee is presented with twelve cards containing different numbers of dots. The first six cards contain dots arranged in a random order and the following six cards contain grouped dots. Examinees are asked to count the dots as quickly as possible. The three studies investigating the DCT in dementia and control samples used different scoring methods (see Table 8). Dean et al. (2009) and Boone et al. (2002) used a scoring system whereby the mean ungrouped dot counting time, the mean grouped dot counting time and the error score are summed. They found poor specificity for their dementia samples (33.4%–75%) but perfect specificity for their healthy controls. Rudman et al. (2011) used the scoring recommended by Lezak, Howieson, Loring, and Fischer (2004) which is that suspect effort is considered if the time taken to count the grouped dots is equal to or more than the time required to count the ungrouped dots. They found good specificity (90%) for their mild dementia sample but poor specificity (68%) for their moderate/severe sample. They used this scoring method because the combined score uses two measures of reaction time which they proposed to be inappropriate index to use with dementia samples as individuals with dementia typically experience a reduction in their processing skills. Finger Tapping Test (FTT; Reitan & Wolfson, 1985) The Finger Tapping Test (FTT) is used in neuropsychology both as part of the Halstead–Reitan Neuropsychological Test Battery (HRNB) and as a stand-alone PVT. See Table 9 for the results of the studies investigating the FTT in dementia and controls. The recommended cut-offs for dominant-hand finger tapping (women - ≤28, men ≤35) reveal poor specificity for the dementia groups across the two papers included in this review (69%–87%). Arnold et al. (2005), however, provide various cut-offs for dominant hand, non-dominant hand, summed hands, and difference between hands. They found 100% specificity for male dementia participants using a difference score of ≤−2 and 87% specificity for female dementia participants using a difference score of ≤5. Further analysis revealed differences in specificity values by dementia subgroup such that the dominant hand cut-off of ≤28 for women with Alzheimer’s disease (AD) was 83% while for females with non-AD dementias, the specificity reduced to 64%. Similarly, a cut-off of >41 for the dominant hand identified 100% of men with AD dementia while only 37% of men with non-AD dementias achieved the same score. Embedded PVTs The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS; Randolph et al., 1998) The RBANS is a widely used neurocognitive battery commonly used in the assessment of dementia. Two RBANS embedded measures of effort have been developed: the Effort Index (EI; Silverberg et al., 2007) and the Effort Scale (ES; Novitski et al., 2012). Seven of the eight studies which investigated these embedded indices, examined the utility of the EI, four examined the utility of the ES and one paper compared both the EI and the ES against two novel RBANS embedded indices. RBANS Effort Index (EI; Silverberg et al., 2007) The EI combines performance on two subtests (Digit Span and List Recognition) to produce an “effort index”. A score of greater than 3 is suggestive of non-credible effort. In the development of the EI, it was found that very poor performance on both these subtests was extremely rare in a mixed clinical sample of patients with neurological disorders. See Table 10 for results of studies investigating the EI. All four of the studies which use a reference standard in order to divide participants into credible and non-credible effort groups, investigated the use of the EI. Sensitivity levels for the EI were 0.50, 0.89, 0.93, and 0.95. Unlike the TOMM studies, dementia severity does not appear to explain the differing sensitivity levels found for the EI. Bortnik et al. (2013) who report a sensitivity level of only 0.50 in their “suspect effort” dementia sample also report that this group had a mean MMSE score of 17.9. Compare this to Paulson and colleagues (2015) who found a sensitivity level of 0.93 in a dementia sample with a mean MMSE score of 23.1. It should be noted, however, that the Bortnik et al. (2013) study included a very small sample (n = 9) and scored relatively poorly on the STARD (20/28) due to inadequate reporting. Specificity levels were reported by all seven papers and range from a low of 0.41 (Dunham, Shadi, Sofko, Denney, & Calloway, 2014) to a relative high of 0.69 (Bortnik et al., 2013). Only controls and MCI samples produced acceptable levels of specificity on the EI. RBANS Effort Scale (ES; Novitski et al., 2012) The RBANS Effort Scale is based on the premise that when an individual has genuine memory impairment, their performance on free-recall tasks (List Recall, Story Recall, and Figure Recall subtests) will decline to close to zero before decline in List Recognition is seen. The authors of the ES propose a cut-off of <12 as being suggestive of non-credible effort (the ES calculation is: List Recognition – (List Recall + Story Recall + Figure Recall)) + Digit Span). See Table 11 for studies investigating the ES. The studies investigating the ES scored relatively poorly on the quality checklists due to inadequate and/or missing information making it difficult to examine the results across studies. In the original validation study, Novitski et al. (2012) compared dementia and MCI participants with a poor effort group of mild head injury participants, they report an impressive area under the curve (AUC) of 0.908. The paper scored poorly, however, on the CCAT (21/40) due to inadequate information given regarding data collection, inclusion and exclusion criteria and participant demographic information. Burton and colleagues (2015) compared the ES in AD and non-AD dementias. They found an impressively high specificity level of 0.96 in their AD sample; however, this fell to 0.69 in their non-AD sample. The authors conclude that the ES may be an appropriate effort index to use when assessing effort level in people with a dementia of the Alzheimer’s type, however in clinical practice, effort tests are most likely to be given during the diagnostic process when a person’s diagnosis is as yet unknown. It does raise the issue that the ES is based on the premise that a person’s performance on tests of free recall will decline before their performance on tests of recognition. This profile of impairment is more likely to be seen in AD, which is characterized by a deficit in episodic memory, than in non-AD dementias. Paulson et al. (2015) and Dunham et al. (2014) investigated the ES in both good and suspect effort groups. They found a sensitivity of 0.71 and 0.88 and specificity levels of 0.42 and 0.81, respectively. It is not clear why the studies found very different specificity levels and due to inadequate reporting by the studies it was impossible to investigate whether type of dementia had a bearing on the discrepancy in the results found (i.e., if the reason for the high failure rate in Paulson’s good effort group was due to the majority having a non-AD dementia). Performance Validity Index (PVI; Paulson et al., 2015) and Charleston Revised Index of Effort for RBANS (CRIER; Paulson et al., 2015) Paulson and colleagues evaluated the EI and ES against two novel RBANS embedded indices of effort, the PVI and the CRIER. The PVI cut-off for detecting invalid responding is <42 and is calculated as follows: RBANS PVI: List recall + story recall + figure recall + digit span + list recognition The CRIER cut-off for detecting invalid responding is <24 and is calculated as follows: RBANS CRIER: list recall + story recall + figure recall + digit span + list recognition − GDS The PVI was found to have a sensitivity of 0.82, a specificity of 0.77, and an AUC of 0.90 whilst the CRIER had a sensitivity of 0.84, a specificity of 0.90, and an AUC of 0.94. These are promising results and warrant further research. Reliable Digit Span (RDS; Greiffenstein et al., 1994) Greiffenstein and colleagues (1994) originally derived the RDS from the Digit Span subtest of the Wechsler Adult Intelligence Scale–Revised (Wechsler, 1981) by “summing the longest string of digits repeated without error over two trials under both forward and backward conditions” (pp. 219–220). Table 12 illustrates the results of studies investigating the RDS. RDS specificity was found to be greatly affected by severity of cognitive impairment. It had high specificity for Loring’s dementia (87%), MCI (96%), and control samples (97%) and also for Zenisek’s (2016) MCI sample (94.6%) whilst Kiewel, Wisdom, Bradshaw, Pastorek and Strutt (2012) found high specificity for their mild dementia sample (89%). All of these samples had MMSE scores of 23 or more (except for Zenisek et al., 2016 who used the MoCA). In contrast, with Kiewel’s more impaired groups, the RDS yielded an unacceptably high level of false positives similar to those in the equally impaired Dean et al. (2009) study. Zenisek et al. (2016) divided their sample into subgroups based on type of dementia diagnosed and found differences in specificity levels with a high of 85.2 for dementia with Lewy bodies sample and a low of 73.3 for their frontotemporal dementia sample. Discussion This review included 25 papers examining the diagnostic accuracy of 14 embedded and stand-alone tests of effort in dementia and MCI samples. In particular this review sought to establish which PVTs were most sensitive to non-credible effort whilst being insensitive to the cognitive impairment seen in individuals who meet criteria for these diagnoses. The effort tests which were found to be most sensitive to non-credible effort whilst being least sensitive to dementia-related cognitive impairment were the three PVTs devised by Green (2003, 2004, 2008). The WMT, MSVT, and NV-MSVT go beyond the pass/fail approach of traditional effort tests and instead use profile analysis to determine if the pattern of results which an examinee produces are indicative of poor effort or if they show a “dementia profile.” The vast majority of the studies which investigated these tests found 100% specificity. The only studies which found low levels of specificity for these PVTs were those which calculated Criterion A only and did not use profile analysis to determine effort level (i.e., determined effort level on whether the participants scored below cut-off on the effort tests but did not determine whether a dementia profile was present). The WMT, MSVT, and NV-MSVT therefore appear to be the most appropriate effort tests for use in cognitive assessment when a dementia is queried. These results should be taken as provisional however because, although the evidence is promising there is not a wealth of literature to draw from. It should also be noted that producing a “dementia profile” is not in itself proof of adequate effort and that clinicians should aim to employ a multi-method approach to effort testing such as that devised by Slick et al. (1999) to highlight any inconsistencies between PVT results and information gathered from other sources. Some of the other tests explored in this review were found to have acceptable specificity levels when used with MCI or mild dementia samples such as the TOMM, the Coin in the Hand, and the RDS. These PVTs do, however, lose specificity with more impaired samples. Methodological Limitations of Effort Testing Literature Compared with other areas of research in clinical neuropsychology, effort testing research faces significant methodological challenges because no “gold-standard” exists with which to reliably determine performance validity. Five of the 25 papers included in this review attempted to independently assess effort by use of a reference standard (three used the TOMM, one used the MSVT, and one used the RBANS Effort Scale). The remaining 20 papers either excluded participants who may have had an incentive to feign impairment or they assumed good effort by virtue of the participants having a diagnosis of dementia. This makes it difficult to know what the true false-positive rate actually is. Diagnostic tests should be evaluated in samples that are representative of those with whom the test will be used in practice. The majority of the studies included in this review use a methodology whereby participants with an established dementia are compared to healthy controls. This is likely to lead to bias because the participants included have a more advanced stage of the disease (in this case dementia) than studies using a clinical sample of consecutive referrals to memory clinics. Indeed there appears to be a positive correlation between PVT specificity and severity of cognitive impairment, such that as scores on cognitive tests decrease, so too does the specificity level of a PVT. Also, very few of the studies included samples with a diagnosis of MCI, a population of importance when evaluating the diagnostic accuracy of effort tests in older adults presenting with memory difficulties. Additionally, very few of the studies included in this review were able to assess sensitivity levels because they only included participants who were deemed to exert credible effort from the outset, either due to not being involved in litigation/claiming disability benefits or simply by virtue of having a diagnosis of dementia. Finally, the studies included in this review largely approach the subject of effort in its “malingering” definition whereby examinees are deemed to be feigning impairment. As discussed previously, indications of poor or atypical motivation are not always the result of deliberate malingering, rather there are many reasons for an individual to put forth less than credible effort such as low mood, stress, conversion disorder, medication side effects and fatigue amongst others. The majority of the studies in this review did not assess for these factors. Methodological Limitations of the Current Review This systematic review faced some methodological limitations. First, it was out with the scope of the review to include every study which has investigated the diagnostic utility of PVTs in dementia samples. The current study focused on papers which included dementia/MCI samples as their primary interest. There are, however, other studies which include a dementia sample alongside other clinical samples. Additionally, as previously mentioned, it was also out with the scope of the current review to examine every PVT investigated by the papers included therefore only the PVTs which are known to be most used in clinical practice were reviewed. Finally, some of the studies examined the performance of the PVTs across different cut-offs. It was not possible to review each of these cut-offs therefore those most used in clinical practice were evaluated. Conclusions Future research on the diagnostic accuracy of PVTs in older adults should aim to focus on the recruitment of consecutive referrals to memory clinics and should employ a multi-method approach such as that proposed by Slick et al. (1999). As part of the cognitive test battery, the participants should receive a reference standard (such as the MSVT or NV-MSVT) and the PVT of interest (the index test). The index test should only be calculated once the final diagnosis is known. This method would allow for both sensitivity and specificity of the PVT in question to be investigated because both good effort and suspect effort participants would be included. Future research should also seek to review the diagnostic utility of PVTs across various cut-offs in MCI/dementia samples. Future research may also seek to further evaluate the use of the two new RBANS embedded indices (PVI and CRIER) created by Paulson et al. (2015) as these showed good potential and the RBANS is a commonly used tool in older adult memory clinics. It is also important for future research to look at subtypes of dementia and how profiles of impairment impact PVT performance. It is likely that some of the variation in performance seen across the different studies may be partially accounted for not just by dementia severity but by dementia subtype. Burton et al. (2015) touched on this issue when they found that the Effort Scale had significantly higher specificity in their Alzheimer’s sample (96%) compared to their non-Alzheimer sample (69%). Following the evaluation of the studies in this review, tests which take a hierarchical approach to effort testing such as the WMT, MSVT and the NV-MSVT may be the best PVTs to use in clinical practice given that these tests have been found to be particularly robust in dementia samples (i.e., they have very low false-positive rates). 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Published: Mar 22, 2018

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