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How Much Participant Outcome Data Is Missing from Sight: Findings from a Cohort of Trials Submitted to a German Research Ethics Committee.

ABSTRACT: Study publication bias and outcome reporting bias have been recognised as two threats to the validity of systematic reviews. The purpose of this research was to estimate the proportion of missing participant outcome data from randomised controlled trials (RCTs) due to lack of publication of whole studies and due to outcome data missing within study publications.Data were extracted from protocols of clinical research projects submitted to the research ethics committee of the University of Freiburg (Germany) between 2000 and 2002 and associated fully published articles. The total amount of published and unpublished outcome data from all trial participants was calculated for each trial and the overall proportion of missing data from both unpublished and published trials computed. Full and partially reported outcome data was also taken into consideration. The impact of funding source on missingness was also considered at the trial level. From 308 parallel group trials in the study cohort, 167 were published and 141 were unpublished. Overall, 260,563 participants contributed to a total of 2,618,116 participant outcome data across all trials. About half (47%) of the participant outcome data from the 308 trials was reported in full but at least 81% were partially reported. Of the 19% of participant data that were missing, 4% was attributable to missing data from published trials and 15% from unpublished trials. Commercially funded trials had a higher probability of publication (relative risk 1.20, 95% confidence interval 0.86, 1.67; p = 0.27) but were less likely to fully report all outcomes than non-commercially funded trials (relative risk 0.64, 95% confidence interval 0.30, 1.38; p = 0.26).Missing participant outcome data from both published and unpublished trials is frequent. Clinical trial registration including outcome information not only identifies that clinical trials exist but the systematic examination and monitoring of trial information within a registry can help detect selective reporting of entire studies and of outcome data within studies and possibly prevent it.

SUBMITTER: Kirkham JJ

PROVIDER: S-EPMC4912080 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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How Much Participant Outcome Data Is Missing from Sight: Findings from a Cohort of Trials Submitted to a German Research Ethics Committee.

Kirkham Jamie J JJ Dwan Kerry M KM Blümle Anette A von Elm Erik E Williamson Paula R PR

PloS one 20160617 6

<h4>Background</h4>Study publication bias and outcome reporting bias have been recognised as two threats to the validity of systematic reviews. The purpose of this research was to estimate the proportion of missing participant outcome data from randomised controlled trials (RCTs) due to lack of publication of whole studies and due to outcome data missing within study publications.<h4>Methods and findings</h4>Data were extracted from protocols of clinical research projects submitted to the resear ...[more]

PMID: 27314853

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Project description:OBJECTIVE:The general purpose for ethics consultations is to deliberate on issues on medical and scientific research and act towards the safeguard of the patient's rights and dignity. With the implementation of European Union (EU) Regulation 536/2014 on clinical trials and cost and time-optimization, the nature of consultations and the bodies they are carried out might be to some extent affected. Accordingly, we sought to gain an updated perspective on the current role and current practices of ethics consultations nationwide in both clinical and research settings. METHODS:The study was carried forth by a three-step mixed-method approach: i) review of policies/regulations for ethics committee (EC) nationwide; ii) a structured survey on ethics consultation activity completed by each EC during 2016; iii) incorporated into the third part, a qualitative assessment with a selected sample of 8 key-informants for a semi-structured interview, discussing EC history, the ethics consultation function, and the professional experience of consultants. RESULTS:Review of the policies/regulations promoted by ECs showed that 72,6% (n = 69) of all the ECs (N = 95) being actually capable of providing ethics consultation service by policy. 71 ECs (74.7%) responded to the survey on ethics consultation requests; among them, 48 (67.6%) provided ethics consultations of which 23 (23/48) actually received requests for this service in the year 2016. Many ECs did not have a structured database in place to provide precise figures of requests received in the last year nor of their contents. CONCLUSION:To date, ethics consultation in clinical and research practice is largely underappreciated and not well understood by users. The consultants themselves lack a comprehensive vision of work carried out in their field, and bioethics training programs to keep them updated. Despite clinical ethics consultation services should not necessarily be mandatory, following the recent EU Regulation on clinical trials, institutional ethics consultation bodies should be re-evaluated.

Project description:The informed-consent process should be one of meaningful information exchange between researchers and study participants. One of the responsibilities of research ethics committees is to oversee appropriate informed consent. The committee must consider various matters before deciding whether the process is appropriate, including the adequacy and completeness of the written information provided to study participants, and the process of obtaining informed consent. This study aimed to identify, quantitatively and qualitatively, consent-related issues in different types of malaria proposals submitted to the Faculty of Tropical Medicine, Ethics Committee.This study reviewed proposal documentation submitted to two panels of the Ethics Committee of the Faculty of Tropical Medicine, Mahidol University, from 2011 to 2015. The documentation included proposals, notifications to researchers of review outcomes and ethical issues of concern to committee members. Each element of the informed-consent process was identified and analyzed by study classification, design, and specimen use, including whether the study involved a vulnerable population. Summative content analysis was used to analyze patterns of common issues raised in reviews.Of the 112 proposals reviewed, 63 required an informed consent process. All researchers proposed communicating with their study participants; however, about two-thirds needed to improve their explanations of study procedures (study activities and specimen/data-collection process) to participants. About 40% of the proposals attracted comments on informed-consent process elements--risk and discomfort, vulnerable status, and compensation. Studies that planned to collect or use new/linked specimens raised more issues around informed consent than studies using linked data/records. Studies that involved vulnerable populations raised more issues than those that did not. The committee usually asked researchers to clarify, elaborate, revise, or paraphrase the consent process elements that were considered to involve inadequate information exchange between researcher and study participant.This study aimed to describe lessons for malaria researchers about common informed-consent process issues in different types of malaria proposals. The information and analysis of informed-consent elements should assist the preparation of malaria-research proposals.

Project description:ObjectivesTo assess the completeness of reporting of sample size determinations in unpublished research protocols and to develop guidance for research ethics committees and for statisticians advising these committees.DesignReview of original research protocols.Study selectionUnpublished research protocols for phase IIb, III, and IV randomised clinical trials of investigational medicinal products submitted to research ethics committees in the United Kingdom during 1 January to 31 December 2009.Main outcome measuresCompleteness of reporting of the sample size determination, including the justification of design assumptions, and disagreement between reported and recalculated sample size.Results446 study protocols were reviewed. Of these, 190 (43%) justified the treatment effect and 213 (48%) justified the population variability or survival experience. Only 55 (12%) discussed the clinical importance of the treatment effect sought. Few protocols provided a reasoned explanation as to why the design assumptions were plausible for the planned study. Sensitivity analyses investigating how the sample size changed under different design assumptions were lacking; six (1%) protocols included a re-estimation of the sample size in the study design. Overall, 188 (42%) protocols reported all of the information to accurately recalculate the sample size; the assumed withdrawal or dropout rate was not given in 177 (40%) studies. Only 134 of the 446 (30%) sample size calculations could be accurately reproduced. Study size tended to be over-estimated rather than under-estimated. Studies with non-commercial sponsors justified the design assumptions used in the calculation more often than studies with commercial sponsors but less often reported all the components needed to reproduce the sample size calculation. Sample sizes for studies with non-commercial sponsors were less often reproduced.ConclusionsMost research protocols did not contain sufficient information to allow the sample size to be reproduced or the plausibility of the design assumptions to be assessed. Greater transparency in the reporting of the determination of the sample size and more focus on study design during the ethical review process would allow deficiencies to be resolved early, before the trial begins. Guidance for research ethics committees and statisticians advising these committees is needed.

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How Much Participant Outcome Data Is Missing from Sight: Findings from a Cohort of Trials Submitted to a German Research Ethics Committee.

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How Much Participant Outcome Data Is Missing from Sight: Findings from a Cohort of Trials Submitted to a German Research Ethics Committee.

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