Sample size determinations in original research protocols for randomised clinical trials submitted to UK research ethics committees: review

BMJ: March 21, 2013

Objectives To assess the completeness of reporting of sample size determinations in unpublished research protocols and to develop guidance for research ethics committees and for statisticians advising these committees.

Design Review of original research protocols.

Study selection Unpublished research protocols for phase IIb, III, and IV randomised clinical trials of investigational medicinal products submitted to research ethics committees in the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 measures Completeness of reporting of the sample size determination, including the justification of design assumptions, and disagreement between reported and recalculated sample size. Read more