Background: Pilot trials are miniature researches carried out with the sole aim of acting as the precursor for larger more definitive studies. Abstracts are used to summarize and introduce the findings to the reading audience. There is substantive empirical evidence showing that abstracts, despite their important roles, are not informative enough, lacking the necessary details. This systematic survey was designed to assess the quality of reporting of heart failure pilot trial abstracts. The quality of reporting was defined as the completeness of reporting based on adherence to the CONSORT extension for reporting of pilot trial abstracts. We also identified factors associated with reporting quality. Methods: We searched MEDLINE (PubMed), Cochrane Controlled Trials Register, Scopus, and African-wide information databases for abstracts from heart failure pilot trials in humans published from 1 January 1990 to 30 November 2016. These were assessed to determine the extent of adherence to CONSORT extension checklist for reporting of abstracts of pilot trials. We screened identified studies for inclusion based on title and abstract. Data were independently extracted by two reviewers using the checklist. We used regression analysis to assess the association between completeness of reporting (measured as the number of items in the CONSORT extension checklist for reporting of abstracts in pilot trials contained in each abstract) and factors influencing the quality of the reports. Results: Two hundred and twenty-eight (228) articles were retrieved, of which 92 met the inclusion criteria. The mean CONSORT extension score was 8.3/16 (standard deviation 1.7); the least reported items were the source of funding (1% [1/92]), trial registration (13% [12/92]), randomization sequence (13% [12/92]), number randomized to each arm (16% [15/92]), and number analyzed in each arm (16% [15/92]). Multivariable regression analysis showed that pharmacological intervention pilot trials [incidence rate ratio (IRR) = 0.88; 95% confidence interval (CI), 0.81–0.97] were significantly associated with better reporting. Other factors such as structured abstract (IRR = 1.10; 95% CI, 0.99–1.23) and CONSORT endorsement (IRR = 1.10; 95% CI, 0.99–1.23) only showed minimal relationship with better reporting quality. Conclusion: The quality of reporting of abstracts of heart failure pilot trials was suboptimal. Pharmacological intervention was significantly associated with better reporting. These findings are consistent with previous research on reporting of trials. * Correspondence: firstname.lastname@example.org Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada Biostatistics Unit/FSORC, Father Sean O’Sullivan Research Centre, St Joseph’s Healthcare-Hamilton, 50 Charlton Avenue East, 3rd Floor Martha Wing, Room H325, Hamilton, ON L8N 4A6, Canada Full list of author information is available at the end of the article © The Author(s). 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Isiguzo et al. Pilot and Feasibility Studies (2018) 4:107 Page 2 of 6 Background for reporting of abstracts of pilot trials; (2) identify Numerous challenges confront readers while accessing aspects of the checklist that are consistently reported; the literature; these include but are not limited to the (3) identify factors associated with better reporting of enormous volume of published work, the high cost of abstracts; and (4) determine the quality (completeness) obtaining articles especially in resource-limited settings of abstracts of pilot trials. , and language constraints when articles are not writ- ten in users’ language . The outcome of this has been Methods an over-reliance on abstracts for articles as a one-stop Randomized controlled pilot trials in heart failure published point for most researchers. Abstracts of journal articles from 1 January 1990 to 30 November 2016 were searched or scientific papers often provide readers with an over- for in line with the systematic survey method as previously view of the content of the full article. As a result, described . Abstracts wereselectediftheywerede- researchers tend to rely on abstracts as a concise source scribed as random, randomly allocated, and randomized. of information  and in making decisions on which We searched the MEDLINE (PubMed), Cochrane Con- publications to read in detail . Furthermore, trolled Trials Register, Scopus, and African-wide informa- researchers rely largely on the abstract when deciding tion databases (search strategy in the Additional file 1). We whether to include an article in a systematic review . limited our search to pilot trial reports written in English All these factors make the abstract a key section of the language only. Two reviewers independently screened the scientific publication. It is, therefore, important that identified papers and those finally selected to assess the abstracts of articles are consistent with what is reported quality of reporting of abstracts using the 16 items of in the text and capture essential information. CONSORT extension for reporting of abstract of pilot tri- Randomized control trials (RCT) constitute a signifi- als. We assigned a score of one to an item on the CON- cant portion of clinical studies and most times are the SORT checklist if the item was reported in the abstract. core component for systematic reviews. However, the The overall quality of abstract was calculated as the propor- quality of reporting of RCTs have over the years tion of “yes” responses. We classified abstracts that re- attracted many questions, mostly related to consistency ported all the 16 items in the CONSORT checklist as and completeness of reports . The Consolidated adequate quality reporting. Standard for Reporting of Trials (CONSORT) checklist We hypothesized that pilot trials published in high impact was conceptualized in 1996 to address these issues. Its journals , published in CONSORT-endorsing journals publication and instant acceptance led to revisions in [19, 20], those on pharmacological interventions , stud- 2007 and 2010 [7, 8]. Many journals have adopted the ies with large sample sizes , and industry-funded studies CONSORT checklist, and it has been shown to improve  would have better reporting quality. the quality of reporting RCTs [9–11]. The protocol for this systematic survey  was regis- The overwhelming acceptance of CONSORT checklist tered with PROSPERO (CRD42016049911) and written has led to the development of extensions to incorporate according to the Preferred Reporting Items for System- other types of RCTs. Due to the need to widen the scope atic Reviews and Meta-Analysis Extension for Protocols of the checklist, in 2016, the CONSORT extension (PRISMA-P) . checklist for abstracts of pilot trials was developed to aid adequate reporting of pilot trials , an important but Statistical analysis often neglected arm of medical research . The analysis was with IBM statistical package for social We conducted this systematic survey to evaluate the sciences (IBM SPSS) version 24 (IBM Corp., Armonk, quality of reporting of abstracts of pilot RCTs in heart NY) and STATA 9.0 (College Station, TX). We calculated failure published 1990–2016. Heart failure, defined as a the percentage of trials that scored yes on each of the 16 clinical condition in which the heart does not pump items and the associated 95% confidence interval (CI). blood sufficiently or does so at a higher pressure to We reported categorical variables as count and per- maintain the body’s need [14, 15], has been a prominent centages; continuous variables are summarized as mean cause of cardiovascular disease burden in Africa in the (standard deviation (SD)) or median (interquartile range last two decades [16, 17]. It has also attracted many clin- (IQR)). Incidence risk ratio (IRR) was calculated to iden- ical trials in the last two decades (1990–2016), most of tify factors associated with better reporting. Negative which were preceded by pilot trials . The quality binomial regression was conducted to determine factors reporting is defined as complete reporting of the 16 associated with better reporting quality. items in the CONSORT extension checklist. The aims of this survey are to (1) evaluate the quality Results of reporting of abstracts of pilot RCTs in the past Our search identified 228 articles; after the screening, 26 years (1990–2016), using the CONSORT extension one hundred and thirty-six articles were found to be Isiguzo et al. Pilot and Feasibility Studies (2018) 4:107 Page 3 of 6 ineligible based on several reasons (Fig. 1). A total of 92 (Table 1). Both pharmacological intervention studies and articles from 48 journals were eligible; among these, 12 non-pharmacological intervention studies were 45 (49%), were conference presentations. The three highest respectively; two studies (2%) had both pharmacological contributing journals were European Journal of Heart and non-pharmacological interventions. The abstract Failure (9 articles; 9.8%), American Heart Journal (8 ar- presentation was structured in 80% of the studies. In 62 ticles; (8.7%), Journal of American College of Cardiology of 92 (67%) of the studies, the CONSORT statement was (7 articles; 7.6%), and Journal of Cardiac Failure (7 arti- not endorsed by the publisher. Most (74%) of the studies cles; 7.6%). were conducted at a single site. Study characteristics Quality of reporting of abstracts of pilot trials The estimate of Kappa statistic for inter-rater agreement None of the studies reported all the 16 items in the check- for screening publications for eligibility was 0.82 [95% list (Table 2), the maximum reported number of items was confidence interval (CI), 0.76–0.87]. A majority (71%) of 12, with a mean (SD) of 8.3 (1.7) items. The most reported the studies were published between 2001 and 2016 item was the type of intervention intended for each group Fig. 1 Study flow Isiguzo et al. Pilot and Feasibility Studies (2018) 4:107 Page 4 of 6 Table 1 Characteristics of included papers: n =92 99% (95% CI 91; 99), followed by specified objectives of the pilot trial 94% (95% CI 89; 99) and pre-specified outcome Characteristic Count (%)/median (Q1; Q3) to address pilot trial objectives 97% (95% CI 90; 98). Year of publication The least reported item was funding source 1% 1990–2006 26 (28%) (95% CI 0.16; 6.9); however, 21 of 92 (22.8%) studies re- 2007–2016 66 (72%) ported funding source in the main manuscript but not in Intervention type (n = 90) the abstract. Inadequately reported items include the Pharmacological 45 (49%) randomization method used 13% (95% CI 8; 19), trial regis- Non-pharmacological 45 (49%) tration information 13% (95% CI 7; 21), and the number of participants screened in each arm 16% (95% CI 9; 26). Both pharmacological and 2 (2%) non-pharmacological Recruitment status, an item in the CONSORT checklist that addresses conference presentation, was low with 2% Abstract format (95% CI 5; 8) among the 12 conference abstracts. � Structured 74/92 (80%) Multivariable analysis (Table 3) of factors associated � Unstructured 18/92 (20%) with reporting quality showed pharmacological interven- CONSORT endorsement tion is significantly associated with better reporting qual- � Yes 30/92 (33%) ity (IRR 0.88; 95% CI 0.81; 0.97; p value 0.01), while � No 62/92 (67%) structured abstract (IRR 1.10; 95% CI 0.99; 1.23; p value 0.05) did not have a strong association. Journals Number of sites which endorsed CONSORT was not a significant � Single 61/82 (74%) factor (IRR 1.10; 95% CI 0.99; 1.23; p value 0.06). � Multiple 21/82 (26%) Study duration in months (n = 68) 3.0 (2.6; 6.1) Discussion and conclusions Sample size (n = 88) 41 (24; 88) The CONSORT extension for reporting of abstracts of CONSORT Consolidated Standards of Reporting Trials, Q1 first quartile, Q3 pilot trials was introduced in 2016 to standardize the third quartile reporting of abstracts of such studies. We undertook this Table 2 Publication adherence to CONSORT checklist for abstract of pilot trials n =92 Item Criteria Count Percent (95% CI) Title Identifier Title identifies the study is a randomized controlled pilot trial 65 71 (60; 79) Description Trial design Description of pilot trial design (e.g., parallel or cluster) 30 33 (23; 44) Method Eligibility Eligibility criteria for each participant 81 88 (78; 94) Settings Setting where pilot was conducted 29 32 (22; 47) Interventions Interventions intended for each group 91 99 (91; 99) Objectives Specific objectives of the pilot trial 89 94 (89; 99) Outcomes Pre-specified assessment or measurement to address the 89 97 (90; 98) pilot trial objectives Randomization sequence Describe how participants were allocated to the interventions 12 13 (8; 19) generation Blinding (masking) Whether or not participants, caregivers, and those assessing 20 22 (15; 31) the outcomes were blinded to group assignment Results Number randomized Number of participants screened 15 16 (9; 26) Number randomized to each group for the pilot objectives 41 45 (36; 53) Recruitment Trial status (for conference abstracts) 2 2 (5; 8) Numbers analyzed Number of participants analyzed in each group of pilot objectives 15 16 (11; 24) Harm Important adverse events or side effects 28 30 (23; 39) Conclusion Result interpretation General interpretation of results of pilot trial 80 87(76; 93) Plans Any implication for future trial 20 22 (15; 30) Registration Trial registration Registration number of trial 12 13 (7; 21) Funding Source of funding 1 1 (0.16; 6.9) CI confidence interval Isiguzo et al. Pilot and Feasibility Studies (2018) 4:107 Page 5 of 6 Table 3 Univariate and multivariable analysis of factors Many of the articles were also silent on the blinding, associated with reported items and when used, some failed to state the group blinded in Item Univariate Multivariable the studies. Not being explicit about blinding erodes the integrity and internal validity of the reports, and it is a IRR (95% CI) p value IRR (95% CI) p value potential source of bias among the readers [33, 34]. Year of publication Reporting on harm was low at 28%; this is an essential � 1990–2006 0.99 0.86 1.07 0.74 item as it informs the design and applicability of � 2007–2016 (0.91; 1.08) (0.91; 1.13) intended larger trials. Previously, this safety reporting Intervention type has often been inadequate or neglected . And, in � Pharmacological 0.93 0.07 0.88 0.01 literature, there is highly variable adherence to reporting � Non-pharmacological (0.86; 1.01); (0.81; 0.97) of harm [36, 37]. Abstract format Methodological aspects reported include intervention � Structured 1.11 0.08 1.10 0.05 type, specific objective, and outcomes to be assessed. � Unstructured (0.99; 1.24) (0.99; 1.23) Many of the articles identified them as pilot trials; this CONSORT endorsement was despite the constraint of word limit by journals, a � Yes 1.07 0.12 1.10 0.06 reason often adduced as responsible for not including � No (0.98; 1.16) (0.99; 1.23) this [10, 26, 29]. Also, pilot trials with pharmacological Number of sites intervention, those with structured abstracts, and those � Single 1.08 0.14 1.02 0.62 published in the journal that endorses CONSORT were � Multiple (0.97; 1.22) (0.92; 1.15) more likely to report on the items on the checklist. The Study duration* 1.03 0.02 last point brings to fore why it is important for journals (1.01; 1.06) to have stipulated reporting format to ensure that the Sample size* 1.01 0.63 quality of abstracts’ report is improved. (0.96; 1.07) Our study is limited in scope by using only articles IRR incidence rate ratio, CI confidence interval published in the English language. We also used a re- *Incident rate for change in 1 unit on the log scale cently produced checklist to evaluate publications done survey to gauge the current practice using heart failure by authors who at the time of writing of the articles pilot trials as a sample to track reporting quality probably had no reporting checklist to follow. improvement expected with introduction and adherence In conclusion, the reporting quality of abstracts of to the extension. We found inadequate reporting quality heart failure trial measured by the number of items in keeping with previous articles evaluating adherence to reported was suboptimal; the need to guard against this CONSORT checklist on abstracts [8, 24, 25]. was the reason that informed the introduction of CON- The least reported item was the funding source, simi- SORT extension checklist. The desire is that increasingly lar to findings in a previous study . The full declar- journals will demand adherence to the checklist by ation of funding source in a publication can give the authors. Ultimately, we hope that there will be a marked reader the opportunity to make their own assessment improvement in the quality of report of abstracts in the regarding potential conflict of interest. However, we coming years. noticed that 22/96 of the articles had information on funding in other places rather than the abstract, and this Additional file may not be unrelated to word count stipulation by indi- vidual journals. Often, this poses a challenge to authors Additional file 1: Database search strategies. (DOCX 21 kb) on what to include in abstracts, and there may be the need for CONSORT extension checklist developers to Acknowledgements Godsent Chichebem Isiguzo is on a PhD scholarship of Postgraduate academic consider this limitation. mobility for African Physician-Scientist (PAMAPS), funded under the intra-ACP The randomization sequence was also poorly re- Academic mobility scheme of European Union. ported. It is an item that can provide acceptable com- parability between groups if properly reported. Some Availability of data and materials The data and materials are available on request from the authors. previous studies have commented on this methodo- logical flaw [10, 27–29], explaining that this could be Authors’ contributions because of attachment of more relevance to clinical GI, LT, BM, MZ, and MC made a substantial contribution to the conceptualization than the methodological aspect of RCTs. There has and design, acquisition of data, analysis, and interpretation. GC, LT, and BM have been involved in drafting the manuscript and revising the content for important been corroborating evidence in other studies support- intellectual content. BM, LT, GC, MC, and MZ gave the final approval of the ing a correlation between deficient reporting and poor version to be published. LT, BM, GC, MZ, and MC agreed to be accountable for trial methodology [30–32]. all aspects of the work in ensuring accuracy and intellectual content. Isiguzo et al. Pilot and Feasibility Studies (2018) 4:107 Page 6 of 6 Ethics approval and consent to participate 17. Isiguzo G, Zunza M, Chirehwa M, Mayosi BM, Thabane L. Quality of abstracts The study did not involve any human subjects, so ethics approval or consent of pilot trials in heart failure: a protocol for a systematic survey. Contemp was not required. Clin Trials Commun. 2017;8(Supplement C):258–63. 18. Turner L, Shamseer L, Altman DG, Weeks L, Peters J, Kober T, et al. Consolidated Competing interests standards of reporting trials (CONSORT) and the completeness of reporting of The authors declare that they have no competing interests. randomised controlled trials (RCTs) published in medical journals. Cochrane Database Syst Rev. 2012;11:Mr000030. 19. Thabane L, Chu R, Cuddy K, Douketis J. What is the quality of reporting in Publisher’sNote weight loss intervention studies? A systematic review of randomized Springer Nature remains neutral with regard to jurisdictional claims in controlled trials. Int J Obes. 2007;31(10):1554–9. published maps and institutional affiliations. 20. Samaan Z, Mbuagbaw L, Kosa D, Borg Debono V, Dillenburg R, Zhang S, et al. A systematic scoping review of adherence to reporting guidelines in Author details health care literature. J Multidiscip Healthc. 2013;6:169–88. Department of Medicine, Groote Schuur Hospital and University of Cape 21. Borg Debono V, Zhang S, Ye C, Paul J, Arya A, Hurlburt L, et al. 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