Toward a Common Language for Measuring Patient Mobility in the Hospital: Reliability and Construct Validity of Interprofessional Mobility Measures

Toward a Common Language for Measuring Patient Mobility in the Hospital: Reliability and... Abstract Background The lack of common language among interprofessional inpatient clinical teams is an important barrier to achieving inpatient mobilization. In The Johns Hopkins Hospital, the Activity Measure for Post-Acute Care (AM-PAC) Inpatient Mobility Short Form (IMSF), also called “6-Clicks,” and the Johns Hopkins Highest Level of Mobility (JH-HLM) are part of routine clinical practice. The measurement characteristics of these tools when used by both nurses and physical therapists for interprofessional communication or assessment are unknown. Objective The purposes of this study were to evaluate the reliability and minimal detectable change of AM-PAC IMSF and JH-HLM when completed by nurses and physical therapists and to evaluate the construct validity of both measures when used by nurses. Design A prospective evaluation of a convenience sample was used. Methods The test-retest reliability and the interrater reliability of AM-PAC IMSF and JH-HLM for inpatients in the neuroscience department (n = 118) of an academic medical center were evaluated. Each participant was independently scored twice by a team of 2 nurses and 1 physical therapist; a total of 4 physical therapists and 8 nurses participated in reliability testing. In a separate inpatient study protocol (n = 69), construct validity was evaluated via an assessment of convergent validity with other measures of function (grip strength, Katz Activities of Daily Living Scale, 2-minute walk test, 5-times sit-to-stand test) used by 5 nurses. Results The test-retest reliability values (intraclass correlation coefficients) for physical therapists and nurses were 0.91 and 0.97, respectively, for AM-PAC IMSF and 0.94 and 0.95, respectively, for JH-HLM. The interrater reliability values (intraclass correlation coefficients) between physical therapists and nurses were 0.96 for AM-PAC IMSF and 0.99 for JH-HLM. Construct validity (Spearman correlations) ranged from 0.25 between JH-HLM and right-hand grip strength to 0.80 between AM-PAC IMSF and the Katz Activities of Daily Living Scale. Limitations The results were obtained from inpatients in the neuroscience department of a single hospital. Conclusions The AM-PAC IMSF and JH-HLM had excellent interrater reliability and test-retest reliability for both physical therapists and nurses. The evaluation of convergent validity suggested that AM-PAC IMSF and JH-HLM measured constructs of patient mobility and physical functioning. Patients who are immobilized during hospitalization experience increased disability, mortality, and cost of care.1–6 Patient mobility and activity in the hospital are associated with reduced muscle weakness and physical impairment, decreased thromboembolic disease, lower incidence of atelectasis and pneumonia, and shortened length of stay.7–18 Hence, increasing mobility and activity is important for improving outcomes and reducing health care costs.1–6 Identifying inpatients who are safe and appropriate for mobilization can be challenging.19,20 Systematic assessment of patients’ functional status may assist in identifying patients at risk for poor outcomes due to lack of mobility, which patients are appropriate to mobilize, and if clinician (eg, nurse or physical therapist) assistance is likely needed. Standardized measurement also can provide a common language, across clinician groups (eg, physicians, nurses, and physical therapists) to describe and quantify patient function.21 Such assessment can help identify functional change during the inpatient stay, evaluate the success of interventions designed to reduce functional limitations, and assist in discharge planning.22 We developed a framework for functional assessment and mobility promotion for acute care hospitals in which both nurses and physical therapists use the same instruments. Specifically, the Activity Measure for Post-Acute Care (AM-PAC) Inpatient Mobility Short Form (IMSF), also known as the “6-Clicks” instrument,19 is used to assess limitations in functional mobility, and the Johns Hopkins Highest Level of Mobility (JH-HLM)13 is used for documenting actual mobility levels and setting mobility goals. The interrater reliability and validity of AM-PAC IMSF have been studied when assessed by a physical therapist,19,20 but no evidence exists when the tool is administered by nurses nor for test-retest reliability of either clinician. Moreover, the reliability and construct validity of JH-HLM has not been formally evaluated for any provider type. Hence, within the setting of our adult neuroscience inpatient population, the objectives of this study were to evaluate the reliability and minimal detectable change of AM-PAC IMSF and JH-HLM when completed by nurses and physical therapists, and the construct validity of both measures by nurses. Methods Institutional review board approval for this study was obtained from the Johns Hopkins University Institutional Review Board, and oral informed consent was obtained from patients (participants). The study setting was two 32-bed adult neurological acute hospital inpatient units in an academic medical center in the United States of America. All clinicians (physical therapists and nurses) involved in the reliability portion of the study had completed 30 minutes of training on how to score both tools. The 30-minute training consisted of reviewing how to score the JH-HLM and AM-PAC IMSF tools with sample clinical scenarios (2 cases based on current patients) for group practice. These scenarios were impromptu cases based on the presenters’ clinical experience and were not written down or recorded. This training was conducted in-person to small groups of clinicians (ie, up to 5) by experienced members of the study team. The nurses participating in the construct validity portion of the study had an introduction meeting with the research team for 15 to 20 minutes to introduce the study and confirm participation; they then received training, as a group, on a separate day. This training session lasted 2 hours and included a presentation followed by hands-on practice and case study discussion (2 cases based on current patients) on how to score the different measurements and record the results. Again, these scenarios were also impromptu cases based on the presenters clinical experience and were not written down or recorded. Clinician participants included 4 physical therapists and 13 nurses. The reliability portion of the study involved all 4 physical therapists and 8 of the nurses, while the validity testing involved the remaining 5 nurses. Physical therapists had between 1.5 and 30 years of experience, with a median of 3 years; 3 had a DPT degree. The 13 nurses had between 2 and 33 years of experience, with a median of 3.5; 4 had a bachelor of science in nursing, 6 were certified neuroscience registered nurses, 1 was a certified registered nurse practitioner, 1 had a master in business administration, 1 was an adult/gerontology clinical nurse specialist, and 1 had a master of science in nursing. All training of clinicians and testing of participants was conducted in English. AM-PAC IMSF The AM-PAC IMSF instrument has 6 questions evaluating a person's need for assistance in completing distinct functional mobility activities. Based on observation or professional judgment of the clinician, each question is scored on a 4-point ordinal scale, where a score of 1 indicates that the person is unable to complete the task and 4 indicates that the person is independent in completing that activity. Hence, the raw score ranges from 6–24, with higher scores indicating less functional limitation. Based on item response theory evaluation during development, raw scores are transformed to a standardized score where the mean is 50 and standard deviation is 10.23–25 This standardized score was used in analysis of the present work. JH-HLM The JH-HLM evaluates general mobility, over a fixed observation period (eg, a 12-hour nursing shift or a single session with a physical therapist). Scoring is based on a person's observed activity as a 1-item scale with 8 ordinal response categories. Each category is numbered consecutively where 1 = only lying, 2 = bed activities, 3 = sitting at edge of bed, 4 = transferring to chair, 5 = standing for greater than or equal to 1 minute, 6 = walking 10 or more steps, 7 = walking approximately 7.5 m or more (25 ft or more), and 8 = walking approximately 75 m or more (250 ft or more).13,26 Participants For both reliability and validity portions of this study, the default was for all patients in the neuroscience units to be included except when they met 1 or more of the following exclusions: bed rest due to physician order, requirement for monitoring that precluded mobilization on the day of testing (eg, intracranial pressure monitoring, continuous electroencephalogram monitoring); hemodynamic instability; scheduled to be off the floor for surgery or other procedure; scheduled for hospital discharge on the day of testing; history of combativeness, resistance, or lack of cooperation with mobility; and requiring a mechanical lift to get out of bed. Reliability Protocol Procedure Reliability testing was conducted over 5 nonconsecutive study days in the summer of 2015. On the days of testing, the charge nurse identified all patients meeting eligibility criteria (see above). These participants were then assigned to 1 of 3 clinician teams for the day. Each clinician team consisted of 2 nurses and 1 physical therapist. One of the nurses was designated as the mobility nurse and the other 2 clinicians were designated as observers. Every attempt was made to see each assigned participant twice: once in the morning and once in the afternoon of the same day, similar to the design of prior studies.20,27 During each encounter between a participant and the clinician team, the goal was for the mobility nurse to progress the participant's mobility to the highest level possible (using the JH-HLM as a guide) according to the participant's capacity, fatigue, and willingness. The observation nurse was available assist for participant safety. The physical therapist was instructed not to assist unless there was a safety concern not otherwise managed by the 2 nurses. After the mobility session, each clinician independently scored the AM-PAC IMSF and JH-HLM based on the session. The clinicians were also instructed to also use other sources of information to score the AM-PAC IMSF, including participant self-report, history or documentation in the participant's chart, family report, or verbal report from the participant's nurse. Clinicians were instructed specifically not to discuss or share their scores with each other. Data analysis The internal consistency measure of reliability of the AM-PAC IMSF scores was evaluated separately for scores recorded by physical therapists and by nurses using the Cronbach alpha statistic. Interrater agreement for each item in the AM-PAC IMSF was calculated using a linearly weighted kappa value by comparing the physical therapist to nurse raw score.28 Test-retest reliability for the total standardized AM-PAC IMSF score and the JH-HLM score was calculated separately for physical therapists, observation nurses, and mobility nurses by comparing morning test scores to afternoon test scores, using a 1-way random-effects intraclass correlation coefficient (ICC) model. Overall interrater reliability for total standardized AM-PAC IMSF and JH-HLM scores was calculated in a single analysis by comparing the morning scores of all 3 clinicians to the afternoon scores of all 3 clinicians using a 2-way random-effects ICC model. Interrater reliability for pairs of clinician types (physical therapist to mobility nurse, physical therapist to observation nurse, and observation nurse to mobility nurse) was calculated using a 2-way random-effects ICC model. To have a power of 0.80 with a minimum test-retest ICC of 0.85, a sample size of 57 was calculated. To account for possible dropout an additional 15 participants were planned. This sample size would provide 114 assessments for the linearly weighted kappa analysis and give it a power of 0.92 at a minimum value of 0.70. The standard error of measurement (SEM) and minimal detectable change (MDC) at the 95% confidence level (MDC95) provided an estimate of the minimum change in score that would be beyond the measurement error of the tools. The SEM was calculated using the ICC and standard deviation obtained from the test-retest of clinician morning to afternoon scores, according to the following formula: SEM = SD × [√(1 − ICC)].29,30 The MDC95 was calculated using this SEM according to the following formula: MDC95 = 1.96 × SEM × (√2).29,30 Construct Validity Protocol Study measures Construct validity was evaluated by comparing the AM-PAC IMSF and JH-HLM against 4 other related measures that can be feasibility evaluated in the hospital setting as described herein. First, grip strength (Jamar handgrip dynamometer; Sammons Preston, Rolyan, Bolingbrook, Illinois) was selected due to its association with impaired functional status,31–35 and evaluated as the mean of 3 measurements taken in each hand. Second, the Katz Activities of Daily Living (ADL) Scale was used.36 This measure has a range of 0 to 6, with higher scores indicating greater independence in physical functioning on the following ADLs: bathing, dressing, toileting, transferring, continence, and feeding. Third, the 2-minute walk test (2MWT) was performed with the total distance walked being recorded in feet.37 Fourth, a 5-times sit-to-stand (5TSTS) test was performed, with the time to complete recorded.38 We followed protocols similar to others for administering all tests in this setting.19,20,31,35–38 Grip strength was recorded as the mean of 3 measurements from each hand, alternating between hands (eg, right hand, left hand, right hand). The Katz ADL Scale was scored based on observation, discussion with the participant, family, and/or the nurse caring for the participant that day. For the 2MWT, participants initially rested in a chair for more than 10 minutes, wore shoes or hospital-issued socks, and were allowed to use their usual walking aid. For the 5TSTS test, more than 2 minutes of rest preceded testing. The participant was seated in a wheelchair, mobility aids were not used, and participants were not allowed to use their arms to push up or lower down. Finally, the AM-PAC IMSF and JH-HLM were scored as described previously (see earlier section on reliability). Procedure Construct validity testing was conducted over 7 nonconsecutive study days during a 3-week period in spring 2016. On testing days, the charge nurse identified all eligible patients. These participants were then assigned to the nurse research team for that day, consisting of 2 nurses and a research coordinator. One of the nurses was designated as the measurement nurse and the other as the assistant nurse. The measurement nurse communicated with the participant, performed testing, recorded results, and communicated with other care providers on the unit. During each encounter between a participant and the research team, the goal was to conduct testing in the following order: grip strength, Katz ADL Scale, 2MWT, 5TSTS test, JH-HLM, and AM-PAC IMSF. If the measurement nurse needed additional assistance to perform a particular test, the assistant nurse was available. During each encounter, the research coordinator was not to assist with testing, unless there was a safety concern not managed by the 2 nurses. Data analysis The Spearman rank order correlation coefficient (ρ) was used to evaluate the association between the standardized AM-PAC IMSF and JH-HLM scores and other tests. Fair (0.25–0.50) to moderate (0.51–0.75) correlations were expected. To have a power of 0.80 with a minimum correlation of 0.3, a sample size of 56 was calculated. To account for possible dropout an additional 14 participants were planned. Role of the Funding Source This research was supported by a Foundation for Physical Therapy Center of Excellence in Physical Therapy Health Services and Health Policy research and training grant. E.H. Hoyer was supported by an internal grant within Johns Hopkins University, Baltimore, Maryland. D.L. Young is a part-time faculty fellow with the Center on Health Services Training and Research (CoHSTAR), which provided financial support to the University of Nevada, Las Vegas, for this project. The funding sources played no role, beyond giving protected research time and travel support to Drs Hoyer and Young, in the conduct of the study. Results Reliability A total of 118 participants were evaluated by 4 physical therapists and 8 nurses. There were no falls or other safety events during this portion of the testing protocol. Participant characteristics are presented in Table 1. The mean test scores by clinician type are presented in Table 2. For the AM-PAC IMSF, the minimum and maximum observed scores were 22.61 and 57.68, and the possible range was 16.59 to 57.68. For the JH-HLM, the minimum and maximum observed scores were 1 and 8, and the possible range was 1 to 8. Table 1. Participant Characteristics by Protocola Characteristic  Reliability Protocol (n = 118)  Construct Validity Protocol (n = 69)  Age, y, X—(SD)  56.6 (15.5)  53.2 (16.6)  Women  65 (55)  32 (46)  Race (white)  71 (60)  43 (62)  Diagnosis  Spinal surgery  30 (25)  19 (28)  Craniotomy  28 (24)  13 (19)  Stroke  11 (9)  10 (14)  Infection  8 (7)  1 (1)  Degenerative disease  7 (6)  3 (4)  Other neurological condition  34 (29)  23 (33)  Characteristic  Reliability Protocol (n = 118)  Construct Validity Protocol (n = 69)  Age, y, X—(SD)  56.6 (15.5)  53.2 (16.6)  Women  65 (55)  32 (46)  Race (white)  71 (60)  43 (62)  Diagnosis  Spinal surgery  30 (25)  19 (28)  Craniotomy  28 (24)  13 (19)  Stroke  11 (9)  10 (14)  Infection  8 (7)  1 (1)  Degenerative disease  7 (6)  3 (4)  Other neurological condition  34 (29)  23 (33)  aData are reported as number (percentage) of participants unless otherwise noted. View Large Table 2. Mean Test Scores by Clinician Typea Test  Clinician Type  Morning Numberb  Morning Score, (SD)  Afternoon Numberb  Afternoon Score, (SD)  AM-PAC IMSF  Physical therapists  93  46.4 (8.1)  89  47.5 (8.9)    Nurses  93  48.4 (9.5)  86  49.1 (9.8)  JH-HLM  Physical therapists  97  6.7 (1.6)  91  6.9 (1.6)    Nurses  97  6.7 (1.7)  91  6.9 (1.6)  Test  Clinician Type  Morning Numberb  Morning Score, (SD)  Afternoon Numberb  Afternoon Score, (SD)  AM-PAC IMSF  Physical therapists  93  46.4 (8.1)  89  47.5 (8.9)    Nurses  93  48.4 (9.5)  86  49.1 (9.8)  JH-HLM  Physical therapists  97  6.7 (1.6)  91  6.9 (1.6)    Nurses  97  6.7 (1.7)  91  6.9 (1.6)  aAM-PAC IMSF = Activity Measure for Post-Acute Care Inpatient Mobility Short Form, JH-HLM = Johns Hopkins Highest Level of Mobility. bNot all participants were available for both morning and afternoon assessments. View Large The internal consistency reliability evaluation of the AM-PAC IMSF scores recorded by physical therapists was 0.94 (95% CI = 0.92–0.96 and for scores recorded by nurses was 0.96 (95% CI = 0.94–0.97). The linearly weighted kappa values for item agreement ranged from .68 (95% CI = 0.57–0.78) for moving to sit edge of bed to 0.76 (95% CI = 0.67–0.85) for bed/chair transfer (Tab. 3). The test-retest and interrater correlation statistics (ICC) for AM-PAC IMSF ranged from 0.91 to 0.96 (Tab. 4). The test-retest and interrater correlation statistics (ICC) for JH-HLM ranged from 0.92 to 0.99 (Tab. 5). The overall AM-PAC IMSF ICC was 0.97 (95% CI = 0.96–0.98), while the AM-PAC IMSF SEM was 1.6 and the MDC95 was 4.5. The overall JH-HLM ICC was 0.99 (95% CI = 0.98–0.99), while the JH-HLM SEM was 0.2 and the MDC95 was 0.6. Table 3. AM-PAC IMSF Item Agreement Between Nurses and Physical Therapistsa       95% CI  Item  No. of Participants  Weighted Kappab  Lower Bound  Upper Bound  Bed mobility  118  0.71  0.61  0.82  Chair sit/stand  118  0.70  0.61  0.80  Lying to sitting on edge of bed  118  0.68  0.57  0.78  Bed/chair transfer  118  0.76  0.67  0.85  Walking  118  0.70  0.60  0.80  3–5 stairs  118  0.69  0.60  0.78        95% CI  Item  No. of Participants  Weighted Kappab  Lower Bound  Upper Bound  Bed mobility  118  0.71  0.61  0.82  Chair sit/stand  118  0.70  0.61  0.80  Lying to sitting on edge of bed  118  0.68  0.57  0.78  Bed/chair transfer  118  0.76  0.67  0.85  Walking  118  0.70  0.60  0.80  3–5 stairs  118  0.69  0.60  0.78  aAM-PAC IMSF = Activity Measure for Post-Acute Care Inpatient Mobility Short Form. bLinear weighting, comparing nurse score with physical therapist score for each item. View Large Table 4. AM-PAC IMSF Interrater and Test-Retest Reliabilitya       95% CI  Type of Evaluation  No. of Participantsb  ICC  Lower Bound  Upper Bound  Test-retest  Physical therapist morning–physical therapist afternoon  64  0.91  0.86  0.95  Mobility RN morning–mobility RN afternoon  59  0.93  0.89  0.96  Observation RN morning–observation RN afternoon  60  0.96  0.93  0.98  Interrater  Physical therapist morning–mobility RN morning  87  0.93  0.89  0.95  Physical therapist afternoon–mobility RN afternoon  83  0.95  0.93  0.97  Physical therapist morning–observation RN morning  87  0.91  0.86  0.94  Physical therapist afternoon–observation RN afternoon  86  0.95  0.91  0.97  Mobility RN morning–observation RN morning  87  0.94  0.91  0.96  Mobility RN afternoon–observation RN afternoon  83  0.94  0.90  0.96        95% CI  Type of Evaluation  No. of Participantsb  ICC  Lower Bound  Upper Bound  Test-retest  Physical therapist morning–physical therapist afternoon  64  0.91  0.86  0.95  Mobility RN morning–mobility RN afternoon  59  0.93  0.89  0.96  Observation RN morning–observation RN afternoon  60  0.96  0.93  0.98  Interrater  Physical therapist morning–mobility RN morning  87  0.93  0.89  0.95  Physical therapist afternoon–mobility RN afternoon  83  0.95  0.93  0.97  Physical therapist morning–observation RN morning  87  0.91  0.86  0.94  Physical therapist afternoon–observation RN afternoon  86  0.95  0.91  0.97  Mobility RN morning–observation RN morning  87  0.94  0.91  0.96  Mobility RN afternoon–observation RN afternoon  83  0.94  0.90  0.96  aAM-PAC IMSF = Activity Measure for Post-Acute Care Inpatient Mobility Short Form, ICC = intraclass correlation coefficient, RN = registered nurse. bNot all participants were available for both morning and afternoon assessments. View Large Table 5. JH-HLM Interrater and Test-Retest Reliabilitya       95% CI  Type of Evaluation  No. of Participantsb  ICC  Lower Bound  Upper Bound  Test-retest  Physical therapist morning–physical therapist afternoon  70  0.94  0.90  0.96  Mobility RN morning–mobility RN afternoon  70  0.92  0.87  0.95  Observation RN morning–observation RN afternoon  70  0.93  0.89  0.96  Interrater  Physical therapist morning–mobility RN morning  97  0.98  0.97  0.98  Physical therapist afternoon–mobility RN afternoon  91  0.99  0.98  0.99  Physical therapist morning–observation RN morning  97  0.99  0.99  0.99  Physical therapist afternoon–observation RN afternoon  91  0.99  0.98  0.99  Mobility RN morning–observation RN morning  97  0.97  0.96  0.98  Mobility RN afternoon–observation RN afternoon  91  0.98  0.97  0.99        95% CI  Type of Evaluation  No. of Participantsb  ICC  Lower Bound  Upper Bound  Test-retest  Physical therapist morning–physical therapist afternoon  70  0.94  0.90  0.96  Mobility RN morning–mobility RN afternoon  70  0.92  0.87  0.95  Observation RN morning–observation RN afternoon  70  0.93  0.89  0.96  Interrater  Physical therapist morning–mobility RN morning  97  0.98  0.97  0.98  Physical therapist afternoon–mobility RN afternoon  91  0.99  0.98  0.99  Physical therapist morning–observation RN morning  97  0.99  0.99  0.99  Physical therapist afternoon–observation RN afternoon  91  0.99  0.98  0.99  Mobility RN morning–observation RN morning  97  0.97  0.96  0.98  Mobility RN afternoon–observation RN afternoon  91  0.98  0.97  0.99  aICC = intraclass correlation coefficient, JH-HLM = Johns Hopkins Highest Level of Mobility, RN = registered nurse. bNot all participants were available for both morning and afternoon assessments. View Large Construct Validity A total of 69 participants and 5 nurses participated in construct validity evaluation. All participants completed at least 1 test and their characteristics are presented in Table 1. All patients who were in the units on the day of testing and did not meet exclusion criteria were approached and agreed to participate. With regard to safety, 2 of the tests (5TSTS test and 2MWT) were terminated because participants reported increased dizziness or pain. The results of the 5TSTS test for these participants were then not available for analysis; however, all other tests for these participants were included. There were no falls or other safety events. Four of 69 participants (5.8%) were unable to complete left grip strength testing due to profound left-side weakness. Eleven of 69 participants (15.9%) were unable to complete the 2MWT: 8 cited weakness, 2 declined, and 1 had a leg amputation and limited ambulatory ability. Nineteen of 69 participants (27.5%) were unable to complete the 5TSTS test: 10 cited weakness, 6 declined, and 1 each had pain, dizziness, and an interruption for other medical care. Spearman correlations are reported in Table 6; all correlations were statistically significant and ranged from 0.25 between JH-HLM and right grip strength to 0.80 between AM-PAC IMSF and Katz ADL Scale. Table 6. Assessment of Construct Validity of AM-PAC IMSF and JH-HLMa       Spearman Correlation (95% CI) for:  Measurement Instrument  No. of Participantsb  (SD)  AM-PAC IMSF  JH-HLM  AM-PAC IMSF  69  49.0 (10.7)    0.65 (0.49 to 0.77)  JH-HLM  69  7.2 (1.5)  0.65 (0.49 to 0.77)    Right grip strength (lb)  69  71.2 (28.5)  0.31 (0.08 to 0.48)  0.25 (0.01 to 0.46)  Left grip strength (lb)  65  66.4 (26.9)  0.30 (0.06 to 0.51)  0.33 (0.09 to 0.53)  Katz ADL Scale  69  4.2 (2.0)  0.80 (0.70 to 0.87)  0.61 (0.44 to 0.74)  2-minute walk test (s)  58  267.8 (172.9)  0.73 (0.58 to 0.83)  0.48 (0.25 to 0.66)  5-times sit-to-stand test (s)  50  31.5 (26.3)  −0.69 (−0.81 to −0.51)  −0.55 (−0.72 to −0.32)        Spearman Correlation (95% CI) for:  Measurement Instrument  No. of Participantsb  (SD)  AM-PAC IMSF  JH-HLM  AM-PAC IMSF  69  49.0 (10.7)    0.65 (0.49 to 0.77)  JH-HLM  69  7.2 (1.5)  0.65 (0.49 to 0.77)    Right grip strength (lb)  69  71.2 (28.5)  0.31 (0.08 to 0.48)  0.25 (0.01 to 0.46)  Left grip strength (lb)  65  66.4 (26.9)  0.30 (0.06 to 0.51)  0.33 (0.09 to 0.53)  Katz ADL Scale  69  4.2 (2.0)  0.80 (0.70 to 0.87)  0.61 (0.44 to 0.74)  2-minute walk test (s)  58  267.8 (172.9)  0.73 (0.58 to 0.83)  0.48 (0.25 to 0.66)  5-times sit-to-stand test (s)  50  31.5 (26.3)  −0.69 (−0.81 to −0.51)  −0.55 (−0.72 to −0.32)  aAM-PAC IMSF = Activity Measure for Post-Acute Care Inpatient Mobility Short Form, JH-HLM = Johns Hopkins Highest Level of Mobility. For grip strength, 1 lb = 0.45 kg bNot all participants were able to complete all tests. View Large Discussion In this prospective study, we evaluated the measurement characteristics of the AM-PAC IMSF and JH-HLM tools in 2 neuroscience units at an academic medical center. Both tools have excellent interrater and test-retest reliability when scored by either physical therapists or nurses. Convergent validity evaluation suggests that the AM-PAC IMSF and JH-HLM measure constructs of patient mobility and physical functioning. In concert with prior studies, these findings support the use of these tools as a common language for interprofessional assessment of patient mobility and functional limitation in the hospital setting.19,20 Interrater and test-retest reliability for both AM-PAC IMSF and JH-HLM were very high for nurses and for physical therapists. The AM-PAC IMSF interrater reliability was slightly higher than prior reports, with no published values for test-retest reliability currently existing.20 The SEM and MDC (sometimes called smallest detectable change30 or minimal detectable difference20) provide information on how different 2 scores would need to be to be beyond the error in the measurements, but not whether the difference is clinically meaningful. In the present study, the AM-PAC IMSF SEM was 1.62 and the MDC95 was 4.49; these values are smaller than previously reported.20 These data will be useful for researchers designing innovative interventions to improve patient mobility and physical functioning in hospital-based clinical trials as well as to help clinicians monitor changes in patient mobility during hospitalization. The interrater reliability between nurses was a novel aspect of this study. A concern frequently expressed by nurses at The Johns Hopkins Hospital is scoring the question about the patient's ability to climb stairs. However, the reliability of this question was higher than the item about the patient moving from lying to sitting edge of bed, which indicates that nurses score this question similarly to physical therapists and are consistent with other nurses. Compared to the AM-PAC IMSF, reliability for JH-HLM was even higher, likely because the distinction between JH-HLM ordinal categories is clear and objective; for example, either patients can walk more than 10 steps but less than approximately 7.5 m (25 ft) or they cannot. Despite the slightly higher average reliability for the JH-HLM, both tools have such high reliability that we would not conclude that one was better than the other in this regard. Findings from the construct validity evaluation of the AM-PAC IMSF and JH-HLM provide evidence that they are measuring related, but not identical, constructs. The highest correlation was between the Katz ADL Scale and the AM-PAC IMSF. Even though the AM-PAC IMSF is focused on mobility19 and the Katz ADL Scale items are mainly activities of daily living,36 the strong correlation suggests that underlying construct(s) measured by both tools are similar. The correlations between the 5TSTS test and both AM-PAC IMSF and JH-HLM were consistent with the expectation that as patient function and mobility level increase, the time it takes them to complete the task goes down. Fair correlations between grip strength and AM-PAC IMSF and JH-HLM are supportive of strength being an important contributing aspect of function and mobility, but not the only construct measured by these tools, as previously reported.39 In designing the order of testing there was concern about patient fatigue and tolerance particularly with the 2MWT and the 5TSTS test and how these fatiguing tests could influence the others. For this reason, these tests were placed last. The scores on these tests may have been higher if they were earlier in the protocol, but this is unlikely to change the relative value and direction of the correlations or our conclusions. When we designed this study, at The Johns Hopkins Hospital nurses were scoring both JH-HLM and AM-PAC IMSF, whereas physical therapists were only scoring the AM-PAC IMSF so the validity testing was fully conducted by nurses. Testing the validity of JH-HLM among physical therapists will be considered for future work. Additionally, the reliability and validity of the Katz ADL Scale has been specifically tested among nurses,40 but we were unable to find similar studies for the other tests. The 2-hour training that our testers received for administering these other tests may have reduced any measurement error; however, the lack of empirical evidence for nurse reliability when scoring grip strength, 2MWT, and 5TSTS test should be considered when evaluating these results. There are a variety of tools and methods that already exist to assess functional limitation and mobility of hospitalized patients, but it is rare that the same tools are used in an interprofessional manner.41–54 At The Johns Hopkins Hospital the AM-PAC IMSF and JH-HLM provide a consistent and simple interprofessional solution to measure functional limitations and mobility. These tools are currently being used in a complimentary manner, with AM-PAC IMSF providing an assessment of functional limitation and the JH-HLM used for documenting observed patient mobility and to set mobility goals.13,26 Use of the JH-HLM in a quality improvement framework has already been shown beneficial for increasing patient mobility in a hospitalized medicine population.13 During hospitalization, patients may have many providers, so having a reliable method to quickly share their mobility level and goals can ensure effective and efficient communication, and avoid overlooking patients who are declining in status and risk for associated immobility harms.1–18 There was little difference between morning and afternoon assessments, suggesting that when a patient experiences a sudden drop in their JH-HLM or AM-PAC IMSF score, clinicians should actively investigate the cause of the change. A drop in the mobility score beyond the MDC (AM-PAC IMSF = 4.5; JH-HLM = 0.6) may represent real change and could help clinicians decide when and how urgently to respond. Moreover, since other AM-PAC short-forms can be used in other care settings (eg, outpatient care, home care), their standardized scores can be used to communicate across the continuum.19,20,55,56 Lastly, the present study highlights that only short educational sessions were required to train providers in administering the JH-HLM and AM-PAC IMSF in a reliable manner, making them attractive tools for inpatient care. This study has potential limitations. First, these results may have limitations in generalizability since they were collected from a small group of providers and patients in 2 neuroscience units at a single academic medical center. It may be valuable to test the performance of these tools on other patient populations and provider types such as occupational therapists; however, the participants had a broad range of functional impairments, mobility levels, and a variety of surgical, neurologic, and medical diagnoses even though they all had primary neurological diagnoses. Additionally, these results were very similar to those previously published on AM-PAC IMSF from a larger patient sample with different diagnoses.19,20 Second, having 1 clinician interact with the participant while the others observed, does not allow for truly independent administration of the scoring protocol. It would have been ideal for each clinician to visit the participant, independently interact with him or her, and produce scores; however, participant tolerance for repeated mobility sessions in this setting prevented this design, and such a testing arrangement may lead to participant fatigue and unintended change in physical performance. Third, 1 of our exclusion criteria was a “history of combativeness, resistance or uncooperativeness with mobility.” To evaluate cognition, nurses assessed participant alertness and orientation, and performed the Glasgow Coma Scale on every participant each shift; however, formal cognitive assessment was not performed to determine inclusion or exclusion for this study. Fourth, the total number of eligible and ineligible participants was not collected to compare with the final number enrolled. Although this introduces the potential for selection bias, different charge nurses were involved in assisting with participant selection on the study days and were not aware of the primary aims of the study. Fifth, the dropout rate for the 5TSTS test was greater than expected, reducing the overall sample size for that test. This may have reduced the precision of those estimates, but the values were within the range expected and statistically significant, indicating sufficient power in the analysis. Finally, it is possible that clinicians scoring participants in the morning and afternoon remembered the previous scores of individual participants, inflating the test-retest reliability. The decision of designing the study for same-day retesting was made because the clinical status of patients can change rapidly in the acute care setting and is expected to affect their mobility as well. In conclusion, the AM-PAC IMSF and JH-HLM had excellent reliability when scored by either physical therapists or nurses in the hospital setting. Validity evaluation of AM-PAC IMSF and JH-HLM suggested that they also measure constructs of patient mobility and physical functioning. A systematic approach to interprofessional standardized measurement can provide a common language to describe and quantify patient functional limitation for clinician teams striving to optimize communication in care planning. Author Contributions and Acknowledgments Concept/idea/research design: E.H. Hoyer, L.M. Klein, J. Kreif, S. Hiser, M. Friedman, A. Lavezza, K.S. Chan, D.M. Needham Writing: E.H. Hoyer, D.L. Young, L.M. Klein, K. Shumock, A.M Jette, D.M. Needham Data collection: K. Shumock, S. Hiser Data analysis: E.H. Hoyer, D.L. Young Project management: E.H. Hoyer, D.L. Young, L.M. Klein, J. Kreif, M. Friedman, A. Lavezza Providing facilities/equipment: J. Kreif, A. Lavezza Providing institutional liaisons: J. Kreif Clerical/secretarial support: D.L. Young, J. Kreif, K. Shumock, A. Lavezza Consultation (including review of manuscript before submitting): E.H. Hoyer, D.L. Young, J. Kreif, M. Friedman, A. Lavezza, A.M Jette, K.S. Chan, D.M. Needham E.H. Hoyer and D.L. Young contributed equally to this article. The authors thank the nurse managers, Tenise Shakes, MSN, RN, CNRN, and Angie Feurer, MSN, RN, and the medical director, Johns Probasco, MD, for their administrative support for conducting the studies. Ethics Approval Ethics approval for this study was obtained from the Johns Hopkins University Institutional Review Board, and oral informed consent was obtained from patients. Funding This research was supported by a Foundation for Physical Therapy Center of Excellence in Physical Therapy Health Services and Health Policy research and training grant. E.H. Hoyer was supported by an internal grant within Johns Hopkins University, Baltimore, Maryland. D.L. Young is a part-time faculty fellow with the Center on Health Services Training and Research (CoHSTAR), which provided financial support to the University of Nevada, Las Vegas, for this project. Disclosures The authors completed the ICJME Form for Disclosure of Potential Conflicts of Interest. A.M. Jette is a founder of CREcare, LLC, which licenses and distributes the AM-PAC; he holds stock in the company and receives royalties from Boston University from license fees generated from the AM-PAC. No other competing interests were reported. References 1 Creditor MC. Hazards of hospitalization of the elderly. Ann Intern Med . 1993; 118: 219– 223. Google Scholar CrossRef Search ADS PubMed  2 Covinsky KE, Pierluissi E, Johnston CB. Hospitalization-associated disability: “She was probably able to ambulate, but I’m not sure.” JAMA . 2011; 306: 1782– 1793. Google Scholar CrossRef Search ADS PubMed  3 Brown CJ, Foley KT, Lowman JD et al.   Comparison of posthospitalization function and community mobility in hospital mobility program and usual care patients: a randomized clinical trial. JAMA Intern Med.  2016; 248: 847– 850. 4 Greysen SR. Activating hospitalized older patients to confront the epidemic of low mobility. JAMA Intern Med . 2016; 176: 928– 929. 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Google Scholar CrossRef Search ADS PubMed  31 Ali NA, O’Brien JMJr, Hoffmann SP et al.   Acquired weakness, handgrip strength, and mortality in critically ill patients. Am J Respir Crit Care Med . 2008; 178: 261– 268. Google Scholar CrossRef Search ADS PubMed  32 Fan E. Critical illness neuromyopathy and the role of physical therapy and rehabilitation in critically ill patients. Respir Care . 2012; 57: 933– 946. Google Scholar CrossRef Search ADS PubMed  33 De Jonghe B, Bastuji-Garin S, Durand MC et al.   Respiratory weakness is associated with limb weakness and delayed weaning in critical illness. Crit Care Med . 2007; 35: 2007– 2015. Google Scholar CrossRef Search ADS PubMed  34 Schweickert WD, Pohlman MC, Pohlman AS et al.   Early physical and occupational therapy in mechanically ventilated, critically ill patients: a randomised controlled trial. Lancet . 2009; 373: 1874– 1882. Google Scholar CrossRef Search ADS PubMed  35 Huang M, Chan KS, Zanni JM et al.   Functional status score for the ICU: an international clinimetric analysis of validity, responsiveness, and minimal important difference. Crit Care Med . 2016; 44: e1155– e1164. Google Scholar CrossRef Search ADS PubMed  36 Katz S, Ford AB, Moskowitz RW, Jackson BA, Jaffe MW. Studies of illness in the aged: the index of ADL—a standardized measure of biological and psychosocial function. JAMA . 1963; 185: 914– 919. Google Scholar CrossRef Search ADS PubMed  37 Pin TW. Psychometric properties of 2-minute walk test: a systematic review. Arch Phys Med Rehabil . 2014; 95: 1759– 1775. Google Scholar CrossRef Search ADS PubMed  38 Bohannon RW. Reference values for the five-repetition sit-to-stand test: a descriptive meta-analysis of data from elders. Percept Mot Skills . 2006; 103: 215– 222. Google Scholar CrossRef Search ADS PubMed  39 Needham DM, Wozniak AW, Hough CL et al.   Risk factors for physical impairment after acute lung injury in a national, multicenter study. Am J Respir Crit Care Med.  2014; 189: 1214– 1224. Google Scholar CrossRef Search ADS PubMed  40 Hartigan I. A comparative review of the Katz ADL and the Barthel Index in assessing the activities of daily living of older people. Int J Older People Nurs . 2007; 2: 204– 212. Google Scholar CrossRef Search ADS PubMed  41 Tipping CJ, Bailey MJ, Bellomo R et al.   The ICU Mobility Scale has construct and predictive validity and is responsive: a multicenter observational study. Ann Am Thorac Soc . 2016; 13: 887– 893. Google Scholar CrossRef Search ADS PubMed  42 Hodgson C, Needham D, Haines K et al.   Feasibility and inter-rater reliability of the ICU mobility scale. Heart Lung . 2014; 43: 19– 24. Google Scholar CrossRef Search ADS PubMed  43 Boynton T, Kelly L, Perez A, Miller M, An Y, Trudgen C. Banner Mobility Assessment Tool for nurses: instrument validation. Am J Safe Patient Handl Mov . 2014; 4: 86– 92. 44 Manning DM, Keller AS, Frank DL. Independent Mobility Validation Exam (I-MOVE): a tool for periodic reassessment of fall-risk and discharge planning. In: Abstract and Poster Presentation at SHM (Formerly NAIP) 5th Annual Meeting . Philadelphia, PA: SHM; 2002. 45 Perme C, Nawa RK, Winkelman C, Masud F. A tool to assess mobility status in critically ill patients: the perme intensive care unit mobility score. Methodist Debakey Cardiovasc J . 2014; 10: 41– 49. Google Scholar CrossRef Search ADS PubMed  46 Williams GP, Robertson V, Greenwood KM, Goldie PA, Morris ME. The High-Level Mobility Assessment Tool (HiMAT) for traumatic brain injury, part 2: content validity and discriminability. Brain Inj . 2005; 19: 833– 843. Google Scholar CrossRef Search ADS PubMed  47 Mehrholz J, Wagner K, Rutte K, Meissner D, Pohl M. Predictive validity and responsiveness of the Functional Ambulation Category in hemiparetic patients after stroke. Arch Phys Med Rehabil . 2007; 88: 1314– 1319. Google Scholar CrossRef Search ADS PubMed  48 van Hedel HJA, Dietz V, Curt A. Assessment of walking speed and distance in subjects with an incomplete spinal cord injury. Neurorehabil Neural Repair . 2007; 21: 295– 301. Google Scholar CrossRef Search ADS PubMed  49 Mathias S, Nayak US, Isaacs B. Balance in elderly patients: the “get-up and go” test. Arch Phys Med Rehabil . 1986; 67: 387– 389. Google Scholar PubMed  50 Field-Fote EC, Fluet GG, Schafer SD et al.   The Spinal Cord Injury Functional Ambulation Inventory (SCI-FAI). J Rehabil Med . 2001; 33: 177– 181. Google Scholar CrossRef Search ADS PubMed  51 Smith R. Validation and reliability of the Elderly Mobility Scale. Physiotherapy . 1994; 80: 744– 747. 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Phys Ther . 2007; 87: 385– 398. Google Scholar CrossRef Search ADS PubMed  © 2017 American Physical Therapy Association http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Physical Therapy Oxford University Press

Toward a Common Language for Measuring Patient Mobility in the Hospital: Reliability and Construct Validity of Interprofessional Mobility Measures

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American Physical Therapy Association
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© 2017 American Physical Therapy Association
ISSN
0031-9023
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1538-6724
D.O.I.
10.1093/ptj/pzx110
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Abstract

Abstract Background The lack of common language among interprofessional inpatient clinical teams is an important barrier to achieving inpatient mobilization. In The Johns Hopkins Hospital, the Activity Measure for Post-Acute Care (AM-PAC) Inpatient Mobility Short Form (IMSF), also called “6-Clicks,” and the Johns Hopkins Highest Level of Mobility (JH-HLM) are part of routine clinical practice. The measurement characteristics of these tools when used by both nurses and physical therapists for interprofessional communication or assessment are unknown. Objective The purposes of this study were to evaluate the reliability and minimal detectable change of AM-PAC IMSF and JH-HLM when completed by nurses and physical therapists and to evaluate the construct validity of both measures when used by nurses. Design A prospective evaluation of a convenience sample was used. Methods The test-retest reliability and the interrater reliability of AM-PAC IMSF and JH-HLM for inpatients in the neuroscience department (n = 118) of an academic medical center were evaluated. Each participant was independently scored twice by a team of 2 nurses and 1 physical therapist; a total of 4 physical therapists and 8 nurses participated in reliability testing. In a separate inpatient study protocol (n = 69), construct validity was evaluated via an assessment of convergent validity with other measures of function (grip strength, Katz Activities of Daily Living Scale, 2-minute walk test, 5-times sit-to-stand test) used by 5 nurses. Results The test-retest reliability values (intraclass correlation coefficients) for physical therapists and nurses were 0.91 and 0.97, respectively, for AM-PAC IMSF and 0.94 and 0.95, respectively, for JH-HLM. The interrater reliability values (intraclass correlation coefficients) between physical therapists and nurses were 0.96 for AM-PAC IMSF and 0.99 for JH-HLM. Construct validity (Spearman correlations) ranged from 0.25 between JH-HLM and right-hand grip strength to 0.80 between AM-PAC IMSF and the Katz Activities of Daily Living Scale. Limitations The results were obtained from inpatients in the neuroscience department of a single hospital. Conclusions The AM-PAC IMSF and JH-HLM had excellent interrater reliability and test-retest reliability for both physical therapists and nurses. The evaluation of convergent validity suggested that AM-PAC IMSF and JH-HLM measured constructs of patient mobility and physical functioning. Patients who are immobilized during hospitalization experience increased disability, mortality, and cost of care.1–6 Patient mobility and activity in the hospital are associated with reduced muscle weakness and physical impairment, decreased thromboembolic disease, lower incidence of atelectasis and pneumonia, and shortened length of stay.7–18 Hence, increasing mobility and activity is important for improving outcomes and reducing health care costs.1–6 Identifying inpatients who are safe and appropriate for mobilization can be challenging.19,20 Systematic assessment of patients’ functional status may assist in identifying patients at risk for poor outcomes due to lack of mobility, which patients are appropriate to mobilize, and if clinician (eg, nurse or physical therapist) assistance is likely needed. Standardized measurement also can provide a common language, across clinician groups (eg, physicians, nurses, and physical therapists) to describe and quantify patient function.21 Such assessment can help identify functional change during the inpatient stay, evaluate the success of interventions designed to reduce functional limitations, and assist in discharge planning.22 We developed a framework for functional assessment and mobility promotion for acute care hospitals in which both nurses and physical therapists use the same instruments. Specifically, the Activity Measure for Post-Acute Care (AM-PAC) Inpatient Mobility Short Form (IMSF), also known as the “6-Clicks” instrument,19 is used to assess limitations in functional mobility, and the Johns Hopkins Highest Level of Mobility (JH-HLM)13 is used for documenting actual mobility levels and setting mobility goals. The interrater reliability and validity of AM-PAC IMSF have been studied when assessed by a physical therapist,19,20 but no evidence exists when the tool is administered by nurses nor for test-retest reliability of either clinician. Moreover, the reliability and construct validity of JH-HLM has not been formally evaluated for any provider type. Hence, within the setting of our adult neuroscience inpatient population, the objectives of this study were to evaluate the reliability and minimal detectable change of AM-PAC IMSF and JH-HLM when completed by nurses and physical therapists, and the construct validity of both measures by nurses. Methods Institutional review board approval for this study was obtained from the Johns Hopkins University Institutional Review Board, and oral informed consent was obtained from patients (participants). The study setting was two 32-bed adult neurological acute hospital inpatient units in an academic medical center in the United States of America. All clinicians (physical therapists and nurses) involved in the reliability portion of the study had completed 30 minutes of training on how to score both tools. The 30-minute training consisted of reviewing how to score the JH-HLM and AM-PAC IMSF tools with sample clinical scenarios (2 cases based on current patients) for group practice. These scenarios were impromptu cases based on the presenters’ clinical experience and were not written down or recorded. This training was conducted in-person to small groups of clinicians (ie, up to 5) by experienced members of the study team. The nurses participating in the construct validity portion of the study had an introduction meeting with the research team for 15 to 20 minutes to introduce the study and confirm participation; they then received training, as a group, on a separate day. This training session lasted 2 hours and included a presentation followed by hands-on practice and case study discussion (2 cases based on current patients) on how to score the different measurements and record the results. Again, these scenarios were also impromptu cases based on the presenters clinical experience and were not written down or recorded. Clinician participants included 4 physical therapists and 13 nurses. The reliability portion of the study involved all 4 physical therapists and 8 of the nurses, while the validity testing involved the remaining 5 nurses. Physical therapists had between 1.5 and 30 years of experience, with a median of 3 years; 3 had a DPT degree. The 13 nurses had between 2 and 33 years of experience, with a median of 3.5; 4 had a bachelor of science in nursing, 6 were certified neuroscience registered nurses, 1 was a certified registered nurse practitioner, 1 had a master in business administration, 1 was an adult/gerontology clinical nurse specialist, and 1 had a master of science in nursing. All training of clinicians and testing of participants was conducted in English. AM-PAC IMSF The AM-PAC IMSF instrument has 6 questions evaluating a person's need for assistance in completing distinct functional mobility activities. Based on observation or professional judgment of the clinician, each question is scored on a 4-point ordinal scale, where a score of 1 indicates that the person is unable to complete the task and 4 indicates that the person is independent in completing that activity. Hence, the raw score ranges from 6–24, with higher scores indicating less functional limitation. Based on item response theory evaluation during development, raw scores are transformed to a standardized score where the mean is 50 and standard deviation is 10.23–25 This standardized score was used in analysis of the present work. JH-HLM The JH-HLM evaluates general mobility, over a fixed observation period (eg, a 12-hour nursing shift or a single session with a physical therapist). Scoring is based on a person's observed activity as a 1-item scale with 8 ordinal response categories. Each category is numbered consecutively where 1 = only lying, 2 = bed activities, 3 = sitting at edge of bed, 4 = transferring to chair, 5 = standing for greater than or equal to 1 minute, 6 = walking 10 or more steps, 7 = walking approximately 7.5 m or more (25 ft or more), and 8 = walking approximately 75 m or more (250 ft or more).13,26 Participants For both reliability and validity portions of this study, the default was for all patients in the neuroscience units to be included except when they met 1 or more of the following exclusions: bed rest due to physician order, requirement for monitoring that precluded mobilization on the day of testing (eg, intracranial pressure monitoring, continuous electroencephalogram monitoring); hemodynamic instability; scheduled to be off the floor for surgery or other procedure; scheduled for hospital discharge on the day of testing; history of combativeness, resistance, or lack of cooperation with mobility; and requiring a mechanical lift to get out of bed. Reliability Protocol Procedure Reliability testing was conducted over 5 nonconsecutive study days in the summer of 2015. On the days of testing, the charge nurse identified all patients meeting eligibility criteria (see above). These participants were then assigned to 1 of 3 clinician teams for the day. Each clinician team consisted of 2 nurses and 1 physical therapist. One of the nurses was designated as the mobility nurse and the other 2 clinicians were designated as observers. Every attempt was made to see each assigned participant twice: once in the morning and once in the afternoon of the same day, similar to the design of prior studies.20,27 During each encounter between a participant and the clinician team, the goal was for the mobility nurse to progress the participant's mobility to the highest level possible (using the JH-HLM as a guide) according to the participant's capacity, fatigue, and willingness. The observation nurse was available assist for participant safety. The physical therapist was instructed not to assist unless there was a safety concern not otherwise managed by the 2 nurses. After the mobility session, each clinician independently scored the AM-PAC IMSF and JH-HLM based on the session. The clinicians were also instructed to also use other sources of information to score the AM-PAC IMSF, including participant self-report, history or documentation in the participant's chart, family report, or verbal report from the participant's nurse. Clinicians were instructed specifically not to discuss or share their scores with each other. Data analysis The internal consistency measure of reliability of the AM-PAC IMSF scores was evaluated separately for scores recorded by physical therapists and by nurses using the Cronbach alpha statistic. Interrater agreement for each item in the AM-PAC IMSF was calculated using a linearly weighted kappa value by comparing the physical therapist to nurse raw score.28 Test-retest reliability for the total standardized AM-PAC IMSF score and the JH-HLM score was calculated separately for physical therapists, observation nurses, and mobility nurses by comparing morning test scores to afternoon test scores, using a 1-way random-effects intraclass correlation coefficient (ICC) model. Overall interrater reliability for total standardized AM-PAC IMSF and JH-HLM scores was calculated in a single analysis by comparing the morning scores of all 3 clinicians to the afternoon scores of all 3 clinicians using a 2-way random-effects ICC model. Interrater reliability for pairs of clinician types (physical therapist to mobility nurse, physical therapist to observation nurse, and observation nurse to mobility nurse) was calculated using a 2-way random-effects ICC model. To have a power of 0.80 with a minimum test-retest ICC of 0.85, a sample size of 57 was calculated. To account for possible dropout an additional 15 participants were planned. This sample size would provide 114 assessments for the linearly weighted kappa analysis and give it a power of 0.92 at a minimum value of 0.70. The standard error of measurement (SEM) and minimal detectable change (MDC) at the 95% confidence level (MDC95) provided an estimate of the minimum change in score that would be beyond the measurement error of the tools. The SEM was calculated using the ICC and standard deviation obtained from the test-retest of clinician morning to afternoon scores, according to the following formula: SEM = SD × [√(1 − ICC)].29,30 The MDC95 was calculated using this SEM according to the following formula: MDC95 = 1.96 × SEM × (√2).29,30 Construct Validity Protocol Study measures Construct validity was evaluated by comparing the AM-PAC IMSF and JH-HLM against 4 other related measures that can be feasibility evaluated in the hospital setting as described herein. First, grip strength (Jamar handgrip dynamometer; Sammons Preston, Rolyan, Bolingbrook, Illinois) was selected due to its association with impaired functional status,31–35 and evaluated as the mean of 3 measurements taken in each hand. Second, the Katz Activities of Daily Living (ADL) Scale was used.36 This measure has a range of 0 to 6, with higher scores indicating greater independence in physical functioning on the following ADLs: bathing, dressing, toileting, transferring, continence, and feeding. Third, the 2-minute walk test (2MWT) was performed with the total distance walked being recorded in feet.37 Fourth, a 5-times sit-to-stand (5TSTS) test was performed, with the time to complete recorded.38 We followed protocols similar to others for administering all tests in this setting.19,20,31,35–38 Grip strength was recorded as the mean of 3 measurements from each hand, alternating between hands (eg, right hand, left hand, right hand). The Katz ADL Scale was scored based on observation, discussion with the participant, family, and/or the nurse caring for the participant that day. For the 2MWT, participants initially rested in a chair for more than 10 minutes, wore shoes or hospital-issued socks, and were allowed to use their usual walking aid. For the 5TSTS test, more than 2 minutes of rest preceded testing. The participant was seated in a wheelchair, mobility aids were not used, and participants were not allowed to use their arms to push up or lower down. Finally, the AM-PAC IMSF and JH-HLM were scored as described previously (see earlier section on reliability). Procedure Construct validity testing was conducted over 7 nonconsecutive study days during a 3-week period in spring 2016. On testing days, the charge nurse identified all eligible patients. These participants were then assigned to the nurse research team for that day, consisting of 2 nurses and a research coordinator. One of the nurses was designated as the measurement nurse and the other as the assistant nurse. The measurement nurse communicated with the participant, performed testing, recorded results, and communicated with other care providers on the unit. During each encounter between a participant and the research team, the goal was to conduct testing in the following order: grip strength, Katz ADL Scale, 2MWT, 5TSTS test, JH-HLM, and AM-PAC IMSF. If the measurement nurse needed additional assistance to perform a particular test, the assistant nurse was available. During each encounter, the research coordinator was not to assist with testing, unless there was a safety concern not managed by the 2 nurses. Data analysis The Spearman rank order correlation coefficient (ρ) was used to evaluate the association between the standardized AM-PAC IMSF and JH-HLM scores and other tests. Fair (0.25–0.50) to moderate (0.51–0.75) correlations were expected. To have a power of 0.80 with a minimum correlation of 0.3, a sample size of 56 was calculated. To account for possible dropout an additional 14 participants were planned. Role of the Funding Source This research was supported by a Foundation for Physical Therapy Center of Excellence in Physical Therapy Health Services and Health Policy research and training grant. E.H. Hoyer was supported by an internal grant within Johns Hopkins University, Baltimore, Maryland. D.L. Young is a part-time faculty fellow with the Center on Health Services Training and Research (CoHSTAR), which provided financial support to the University of Nevada, Las Vegas, for this project. The funding sources played no role, beyond giving protected research time and travel support to Drs Hoyer and Young, in the conduct of the study. Results Reliability A total of 118 participants were evaluated by 4 physical therapists and 8 nurses. There were no falls or other safety events during this portion of the testing protocol. Participant characteristics are presented in Table 1. The mean test scores by clinician type are presented in Table 2. For the AM-PAC IMSF, the minimum and maximum observed scores were 22.61 and 57.68, and the possible range was 16.59 to 57.68. For the JH-HLM, the minimum and maximum observed scores were 1 and 8, and the possible range was 1 to 8. Table 1. Participant Characteristics by Protocola Characteristic  Reliability Protocol (n = 118)  Construct Validity Protocol (n = 69)  Age, y, X—(SD)  56.6 (15.5)  53.2 (16.6)  Women  65 (55)  32 (46)  Race (white)  71 (60)  43 (62)  Diagnosis  Spinal surgery  30 (25)  19 (28)  Craniotomy  28 (24)  13 (19)  Stroke  11 (9)  10 (14)  Infection  8 (7)  1 (1)  Degenerative disease  7 (6)  3 (4)  Other neurological condition  34 (29)  23 (33)  Characteristic  Reliability Protocol (n = 118)  Construct Validity Protocol (n = 69)  Age, y, X—(SD)  56.6 (15.5)  53.2 (16.6)  Women  65 (55)  32 (46)  Race (white)  71 (60)  43 (62)  Diagnosis  Spinal surgery  30 (25)  19 (28)  Craniotomy  28 (24)  13 (19)  Stroke  11 (9)  10 (14)  Infection  8 (7)  1 (1)  Degenerative disease  7 (6)  3 (4)  Other neurological condition  34 (29)  23 (33)  aData are reported as number (percentage) of participants unless otherwise noted. View Large Table 2. Mean Test Scores by Clinician Typea Test  Clinician Type  Morning Numberb  Morning Score, (SD)  Afternoon Numberb  Afternoon Score, (SD)  AM-PAC IMSF  Physical therapists  93  46.4 (8.1)  89  47.5 (8.9)    Nurses  93  48.4 (9.5)  86  49.1 (9.8)  JH-HLM  Physical therapists  97  6.7 (1.6)  91  6.9 (1.6)    Nurses  97  6.7 (1.7)  91  6.9 (1.6)  Test  Clinician Type  Morning Numberb  Morning Score, (SD)  Afternoon Numberb  Afternoon Score, (SD)  AM-PAC IMSF  Physical therapists  93  46.4 (8.1)  89  47.5 (8.9)    Nurses  93  48.4 (9.5)  86  49.1 (9.8)  JH-HLM  Physical therapists  97  6.7 (1.6)  91  6.9 (1.6)    Nurses  97  6.7 (1.7)  91  6.9 (1.6)  aAM-PAC IMSF = Activity Measure for Post-Acute Care Inpatient Mobility Short Form, JH-HLM = Johns Hopkins Highest Level of Mobility. bNot all participants were available for both morning and afternoon assessments. View Large The internal consistency reliability evaluation of the AM-PAC IMSF scores recorded by physical therapists was 0.94 (95% CI = 0.92–0.96 and for scores recorded by nurses was 0.96 (95% CI = 0.94–0.97). The linearly weighted kappa values for item agreement ranged from .68 (95% CI = 0.57–0.78) for moving to sit edge of bed to 0.76 (95% CI = 0.67–0.85) for bed/chair transfer (Tab. 3). The test-retest and interrater correlation statistics (ICC) for AM-PAC IMSF ranged from 0.91 to 0.96 (Tab. 4). The test-retest and interrater correlation statistics (ICC) for JH-HLM ranged from 0.92 to 0.99 (Tab. 5). The overall AM-PAC IMSF ICC was 0.97 (95% CI = 0.96–0.98), while the AM-PAC IMSF SEM was 1.6 and the MDC95 was 4.5. The overall JH-HLM ICC was 0.99 (95% CI = 0.98–0.99), while the JH-HLM SEM was 0.2 and the MDC95 was 0.6. Table 3. AM-PAC IMSF Item Agreement Between Nurses and Physical Therapistsa       95% CI  Item  No. of Participants  Weighted Kappab  Lower Bound  Upper Bound  Bed mobility  118  0.71  0.61  0.82  Chair sit/stand  118  0.70  0.61  0.80  Lying to sitting on edge of bed  118  0.68  0.57  0.78  Bed/chair transfer  118  0.76  0.67  0.85  Walking  118  0.70  0.60  0.80  3–5 stairs  118  0.69  0.60  0.78        95% CI  Item  No. of Participants  Weighted Kappab  Lower Bound  Upper Bound  Bed mobility  118  0.71  0.61  0.82  Chair sit/stand  118  0.70  0.61  0.80  Lying to sitting on edge of bed  118  0.68  0.57  0.78  Bed/chair transfer  118  0.76  0.67  0.85  Walking  118  0.70  0.60  0.80  3–5 stairs  118  0.69  0.60  0.78  aAM-PAC IMSF = Activity Measure for Post-Acute Care Inpatient Mobility Short Form. bLinear weighting, comparing nurse score with physical therapist score for each item. View Large Table 4. AM-PAC IMSF Interrater and Test-Retest Reliabilitya       95% CI  Type of Evaluation  No. of Participantsb  ICC  Lower Bound  Upper Bound  Test-retest  Physical therapist morning–physical therapist afternoon  64  0.91  0.86  0.95  Mobility RN morning–mobility RN afternoon  59  0.93  0.89  0.96  Observation RN morning–observation RN afternoon  60  0.96  0.93  0.98  Interrater  Physical therapist morning–mobility RN morning  87  0.93  0.89  0.95  Physical therapist afternoon–mobility RN afternoon  83  0.95  0.93  0.97  Physical therapist morning–observation RN morning  87  0.91  0.86  0.94  Physical therapist afternoon–observation RN afternoon  86  0.95  0.91  0.97  Mobility RN morning–observation RN morning  87  0.94  0.91  0.96  Mobility RN afternoon–observation RN afternoon  83  0.94  0.90  0.96        95% CI  Type of Evaluation  No. of Participantsb  ICC  Lower Bound  Upper Bound  Test-retest  Physical therapist morning–physical therapist afternoon  64  0.91  0.86  0.95  Mobility RN morning–mobility RN afternoon  59  0.93  0.89  0.96  Observation RN morning–observation RN afternoon  60  0.96  0.93  0.98  Interrater  Physical therapist morning–mobility RN morning  87  0.93  0.89  0.95  Physical therapist afternoon–mobility RN afternoon  83  0.95  0.93  0.97  Physical therapist morning–observation RN morning  87  0.91  0.86  0.94  Physical therapist afternoon–observation RN afternoon  86  0.95  0.91  0.97  Mobility RN morning–observation RN morning  87  0.94  0.91  0.96  Mobility RN afternoon–observation RN afternoon  83  0.94  0.90  0.96  aAM-PAC IMSF = Activity Measure for Post-Acute Care Inpatient Mobility Short Form, ICC = intraclass correlation coefficient, RN = registered nurse. bNot all participants were available for both morning and afternoon assessments. View Large Table 5. JH-HLM Interrater and Test-Retest Reliabilitya       95% CI  Type of Evaluation  No. of Participantsb  ICC  Lower Bound  Upper Bound  Test-retest  Physical therapist morning–physical therapist afternoon  70  0.94  0.90  0.96  Mobility RN morning–mobility RN afternoon  70  0.92  0.87  0.95  Observation RN morning–observation RN afternoon  70  0.93  0.89  0.96  Interrater  Physical therapist morning–mobility RN morning  97  0.98  0.97  0.98  Physical therapist afternoon–mobility RN afternoon  91  0.99  0.98  0.99  Physical therapist morning–observation RN morning  97  0.99  0.99  0.99  Physical therapist afternoon–observation RN afternoon  91  0.99  0.98  0.99  Mobility RN morning–observation RN morning  97  0.97  0.96  0.98  Mobility RN afternoon–observation RN afternoon  91  0.98  0.97  0.99        95% CI  Type of Evaluation  No. of Participantsb  ICC  Lower Bound  Upper Bound  Test-retest  Physical therapist morning–physical therapist afternoon  70  0.94  0.90  0.96  Mobility RN morning–mobility RN afternoon  70  0.92  0.87  0.95  Observation RN morning–observation RN afternoon  70  0.93  0.89  0.96  Interrater  Physical therapist morning–mobility RN morning  97  0.98  0.97  0.98  Physical therapist afternoon–mobility RN afternoon  91  0.99  0.98  0.99  Physical therapist morning–observation RN morning  97  0.99  0.99  0.99  Physical therapist afternoon–observation RN afternoon  91  0.99  0.98  0.99  Mobility RN morning–observation RN morning  97  0.97  0.96  0.98  Mobility RN afternoon–observation RN afternoon  91  0.98  0.97  0.99  aICC = intraclass correlation coefficient, JH-HLM = Johns Hopkins Highest Level of Mobility, RN = registered nurse. bNot all participants were available for both morning and afternoon assessments. View Large Construct Validity A total of 69 participants and 5 nurses participated in construct validity evaluation. All participants completed at least 1 test and their characteristics are presented in Table 1. All patients who were in the units on the day of testing and did not meet exclusion criteria were approached and agreed to participate. With regard to safety, 2 of the tests (5TSTS test and 2MWT) were terminated because participants reported increased dizziness or pain. The results of the 5TSTS test for these participants were then not available for analysis; however, all other tests for these participants were included. There were no falls or other safety events. Four of 69 participants (5.8%) were unable to complete left grip strength testing due to profound left-side weakness. Eleven of 69 participants (15.9%) were unable to complete the 2MWT: 8 cited weakness, 2 declined, and 1 had a leg amputation and limited ambulatory ability. Nineteen of 69 participants (27.5%) were unable to complete the 5TSTS test: 10 cited weakness, 6 declined, and 1 each had pain, dizziness, and an interruption for other medical care. Spearman correlations are reported in Table 6; all correlations were statistically significant and ranged from 0.25 between JH-HLM and right grip strength to 0.80 between AM-PAC IMSF and Katz ADL Scale. Table 6. Assessment of Construct Validity of AM-PAC IMSF and JH-HLMa       Spearman Correlation (95% CI) for:  Measurement Instrument  No. of Participantsb  (SD)  AM-PAC IMSF  JH-HLM  AM-PAC IMSF  69  49.0 (10.7)    0.65 (0.49 to 0.77)  JH-HLM  69  7.2 (1.5)  0.65 (0.49 to 0.77)    Right grip strength (lb)  69  71.2 (28.5)  0.31 (0.08 to 0.48)  0.25 (0.01 to 0.46)  Left grip strength (lb)  65  66.4 (26.9)  0.30 (0.06 to 0.51)  0.33 (0.09 to 0.53)  Katz ADL Scale  69  4.2 (2.0)  0.80 (0.70 to 0.87)  0.61 (0.44 to 0.74)  2-minute walk test (s)  58  267.8 (172.9)  0.73 (0.58 to 0.83)  0.48 (0.25 to 0.66)  5-times sit-to-stand test (s)  50  31.5 (26.3)  −0.69 (−0.81 to −0.51)  −0.55 (−0.72 to −0.32)        Spearman Correlation (95% CI) for:  Measurement Instrument  No. of Participantsb  (SD)  AM-PAC IMSF  JH-HLM  AM-PAC IMSF  69  49.0 (10.7)    0.65 (0.49 to 0.77)  JH-HLM  69  7.2 (1.5)  0.65 (0.49 to 0.77)    Right grip strength (lb)  69  71.2 (28.5)  0.31 (0.08 to 0.48)  0.25 (0.01 to 0.46)  Left grip strength (lb)  65  66.4 (26.9)  0.30 (0.06 to 0.51)  0.33 (0.09 to 0.53)  Katz ADL Scale  69  4.2 (2.0)  0.80 (0.70 to 0.87)  0.61 (0.44 to 0.74)  2-minute walk test (s)  58  267.8 (172.9)  0.73 (0.58 to 0.83)  0.48 (0.25 to 0.66)  5-times sit-to-stand test (s)  50  31.5 (26.3)  −0.69 (−0.81 to −0.51)  −0.55 (−0.72 to −0.32)  aAM-PAC IMSF = Activity Measure for Post-Acute Care Inpatient Mobility Short Form, JH-HLM = Johns Hopkins Highest Level of Mobility. For grip strength, 1 lb = 0.45 kg bNot all participants were able to complete all tests. View Large Discussion In this prospective study, we evaluated the measurement characteristics of the AM-PAC IMSF and JH-HLM tools in 2 neuroscience units at an academic medical center. Both tools have excellent interrater and test-retest reliability when scored by either physical therapists or nurses. Convergent validity evaluation suggests that the AM-PAC IMSF and JH-HLM measure constructs of patient mobility and physical functioning. In concert with prior studies, these findings support the use of these tools as a common language for interprofessional assessment of patient mobility and functional limitation in the hospital setting.19,20 Interrater and test-retest reliability for both AM-PAC IMSF and JH-HLM were very high for nurses and for physical therapists. The AM-PAC IMSF interrater reliability was slightly higher than prior reports, with no published values for test-retest reliability currently existing.20 The SEM and MDC (sometimes called smallest detectable change30 or minimal detectable difference20) provide information on how different 2 scores would need to be to be beyond the error in the measurements, but not whether the difference is clinically meaningful. In the present study, the AM-PAC IMSF SEM was 1.62 and the MDC95 was 4.49; these values are smaller than previously reported.20 These data will be useful for researchers designing innovative interventions to improve patient mobility and physical functioning in hospital-based clinical trials as well as to help clinicians monitor changes in patient mobility during hospitalization. The interrater reliability between nurses was a novel aspect of this study. A concern frequently expressed by nurses at The Johns Hopkins Hospital is scoring the question about the patient's ability to climb stairs. However, the reliability of this question was higher than the item about the patient moving from lying to sitting edge of bed, which indicates that nurses score this question similarly to physical therapists and are consistent with other nurses. Compared to the AM-PAC IMSF, reliability for JH-HLM was even higher, likely because the distinction between JH-HLM ordinal categories is clear and objective; for example, either patients can walk more than 10 steps but less than approximately 7.5 m (25 ft) or they cannot. Despite the slightly higher average reliability for the JH-HLM, both tools have such high reliability that we would not conclude that one was better than the other in this regard. Findings from the construct validity evaluation of the AM-PAC IMSF and JH-HLM provide evidence that they are measuring related, but not identical, constructs. The highest correlation was between the Katz ADL Scale and the AM-PAC IMSF. Even though the AM-PAC IMSF is focused on mobility19 and the Katz ADL Scale items are mainly activities of daily living,36 the strong correlation suggests that underlying construct(s) measured by both tools are similar. The correlations between the 5TSTS test and both AM-PAC IMSF and JH-HLM were consistent with the expectation that as patient function and mobility level increase, the time it takes them to complete the task goes down. Fair correlations between grip strength and AM-PAC IMSF and JH-HLM are supportive of strength being an important contributing aspect of function and mobility, but not the only construct measured by these tools, as previously reported.39 In designing the order of testing there was concern about patient fatigue and tolerance particularly with the 2MWT and the 5TSTS test and how these fatiguing tests could influence the others. For this reason, these tests were placed last. The scores on these tests may have been higher if they were earlier in the protocol, but this is unlikely to change the relative value and direction of the correlations or our conclusions. When we designed this study, at The Johns Hopkins Hospital nurses were scoring both JH-HLM and AM-PAC IMSF, whereas physical therapists were only scoring the AM-PAC IMSF so the validity testing was fully conducted by nurses. Testing the validity of JH-HLM among physical therapists will be considered for future work. Additionally, the reliability and validity of the Katz ADL Scale has been specifically tested among nurses,40 but we were unable to find similar studies for the other tests. The 2-hour training that our testers received for administering these other tests may have reduced any measurement error; however, the lack of empirical evidence for nurse reliability when scoring grip strength, 2MWT, and 5TSTS test should be considered when evaluating these results. There are a variety of tools and methods that already exist to assess functional limitation and mobility of hospitalized patients, but it is rare that the same tools are used in an interprofessional manner.41–54 At The Johns Hopkins Hospital the AM-PAC IMSF and JH-HLM provide a consistent and simple interprofessional solution to measure functional limitations and mobility. These tools are currently being used in a complimentary manner, with AM-PAC IMSF providing an assessment of functional limitation and the JH-HLM used for documenting observed patient mobility and to set mobility goals.13,26 Use of the JH-HLM in a quality improvement framework has already been shown beneficial for increasing patient mobility in a hospitalized medicine population.13 During hospitalization, patients may have many providers, so having a reliable method to quickly share their mobility level and goals can ensure effective and efficient communication, and avoid overlooking patients who are declining in status and risk for associated immobility harms.1–18 There was little difference between morning and afternoon assessments, suggesting that when a patient experiences a sudden drop in their JH-HLM or AM-PAC IMSF score, clinicians should actively investigate the cause of the change. A drop in the mobility score beyond the MDC (AM-PAC IMSF = 4.5; JH-HLM = 0.6) may represent real change and could help clinicians decide when and how urgently to respond. Moreover, since other AM-PAC short-forms can be used in other care settings (eg, outpatient care, home care), their standardized scores can be used to communicate across the continuum.19,20,55,56 Lastly, the present study highlights that only short educational sessions were required to train providers in administering the JH-HLM and AM-PAC IMSF in a reliable manner, making them attractive tools for inpatient care. This study has potential limitations. First, these results may have limitations in generalizability since they were collected from a small group of providers and patients in 2 neuroscience units at a single academic medical center. It may be valuable to test the performance of these tools on other patient populations and provider types such as occupational therapists; however, the participants had a broad range of functional impairments, mobility levels, and a variety of surgical, neurologic, and medical diagnoses even though they all had primary neurological diagnoses. Additionally, these results were very similar to those previously published on AM-PAC IMSF from a larger patient sample with different diagnoses.19,20 Second, having 1 clinician interact with the participant while the others observed, does not allow for truly independent administration of the scoring protocol. It would have been ideal for each clinician to visit the participant, independently interact with him or her, and produce scores; however, participant tolerance for repeated mobility sessions in this setting prevented this design, and such a testing arrangement may lead to participant fatigue and unintended change in physical performance. Third, 1 of our exclusion criteria was a “history of combativeness, resistance or uncooperativeness with mobility.” To evaluate cognition, nurses assessed participant alertness and orientation, and performed the Glasgow Coma Scale on every participant each shift; however, formal cognitive assessment was not performed to determine inclusion or exclusion for this study. Fourth, the total number of eligible and ineligible participants was not collected to compare with the final number enrolled. Although this introduces the potential for selection bias, different charge nurses were involved in assisting with participant selection on the study days and were not aware of the primary aims of the study. Fifth, the dropout rate for the 5TSTS test was greater than expected, reducing the overall sample size for that test. This may have reduced the precision of those estimates, but the values were within the range expected and statistically significant, indicating sufficient power in the analysis. Finally, it is possible that clinicians scoring participants in the morning and afternoon remembered the previous scores of individual participants, inflating the test-retest reliability. The decision of designing the study for same-day retesting was made because the clinical status of patients can change rapidly in the acute care setting and is expected to affect their mobility as well. In conclusion, the AM-PAC IMSF and JH-HLM had excellent reliability when scored by either physical therapists or nurses in the hospital setting. Validity evaluation of AM-PAC IMSF and JH-HLM suggested that they also measure constructs of patient mobility and physical functioning. A systematic approach to interprofessional standardized measurement can provide a common language to describe and quantify patient functional limitation for clinician teams striving to optimize communication in care planning. Author Contributions and Acknowledgments Concept/idea/research design: E.H. Hoyer, L.M. Klein, J. Kreif, S. Hiser, M. Friedman, A. Lavezza, K.S. Chan, D.M. Needham Writing: E.H. Hoyer, D.L. Young, L.M. Klein, K. Shumock, A.M Jette, D.M. Needham Data collection: K. Shumock, S. Hiser Data analysis: E.H. Hoyer, D.L. Young Project management: E.H. Hoyer, D.L. Young, L.M. Klein, J. Kreif, M. Friedman, A. Lavezza Providing facilities/equipment: J. Kreif, A. Lavezza Providing institutional liaisons: J. Kreif Clerical/secretarial support: D.L. Young, J. Kreif, K. Shumock, A. Lavezza Consultation (including review of manuscript before submitting): E.H. Hoyer, D.L. Young, J. Kreif, M. Friedman, A. Lavezza, A.M Jette, K.S. Chan, D.M. Needham E.H. Hoyer and D.L. Young contributed equally to this article. The authors thank the nurse managers, Tenise Shakes, MSN, RN, CNRN, and Angie Feurer, MSN, RN, and the medical director, Johns Probasco, MD, for their administrative support for conducting the studies. Ethics Approval Ethics approval for this study was obtained from the Johns Hopkins University Institutional Review Board, and oral informed consent was obtained from patients. Funding This research was supported by a Foundation for Physical Therapy Center of Excellence in Physical Therapy Health Services and Health Policy research and training grant. E.H. Hoyer was supported by an internal grant within Johns Hopkins University, Baltimore, Maryland. D.L. Young is a part-time faculty fellow with the Center on Health Services Training and Research (CoHSTAR), which provided financial support to the University of Nevada, Las Vegas, for this project. Disclosures The authors completed the ICJME Form for Disclosure of Potential Conflicts of Interest. 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Physical TherapyOxford University Press

Published: Feb 1, 2018

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