Sample size determinations in original research protocols for randomised clinical trials submitted to UK research ethics committees: review
BMJPublished 21 March 2013Open access
Timothy Clark, Ursula Berger, Ulrich Mansmann
Citations65
SJR quartileQ1
SJR score2.98
SNIP9.45
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ObjectiveStudy objective
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Sample sizeSample sizes
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TL;DR
Most 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, and guidance for research ethics committees and statisticians advising these committees is needed.
Abstract
Most 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.
Keywords
MathematicsDecision SciencesMedicine
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