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Review
. 2011 May 11:342:d2496.
doi: 10.1136/bmj.d2496.

Inadequate reporting of research ethics review and informed consent in cluster randomised trials: review of random sample of published trials

Monica Taljaard  1 , Andrew D McRae, Charles Weijer, Carol Bennett, Stephanie Dixon, Julia Taleban, Zoe Skea, Martin P Eccles, Jamie C Brehaut, Allan Donner, Raphael Saginur, Robert F Boruch, Jeremy M Grimshaw
Affiliations
Review

Inadequate reporting of research ethics review and informed consent in cluster randomised trials: review of random sample of published trials

Monica Taljaard et al. BMJ. .

Abstract

Objectives: To investigate the extent to which authors of cluster randomised trials adhered to two basic requirements of the World Medical Association's Declaration of Helsinki and the International Committee of Medical Journal Editors' uniform requirements for manuscripts (namely, reporting of research ethics review and informed consent), to determine whether the adequacy of reporting has improved over time, and to identify characteristics of cluster randomised trials associated with reporting of ethics practices.

Design: Review of a random sample of published cluster randomised trials from an electronic search in Medline.

Setting: Cluster randomised trials in health research published in English language journals from 2000 to 2008. Study sample 300 cluster randomised trials published in 150 journals.

Results: 77 (26%, 95% confidence interval 21% to 31%) trials failed to report ethics review. The proportion reporting ethics review increased significantly over time (P<0.001). Trials with data collection interventions at the individual level were more likely to report ethics review than were trials that used routine data sources only (79% (n=151) v 55% (23); P=0.008). Trials that accounted for clustering in the design and analysis were more likely to report ethics review. The median impact factor of the journal of publication was higher for trials that reported ethics review (3.4 v 2.3; P<0.001). 93 (31%, 26% to 36%) trials failed to report consent. Reporting of consent increased significantly over time (P<0.001). Trials with interventions targeting participants at the individual level were more likely to report consent than were trials with interventions targeting the cluster level (87% (90) v 48% (41); P<0.001). Trials with data collection interventions at the individual level were more likely to report consent than were those that used routine data sources only (78% (146) v 29% (11); P<0.001).

Conclusions: Reporting of research ethics protections in cluster randomised trials is inadequate. In addition to research ethics approval, authors should report whether informed consent was sought, from whom consent was sought, and what consent was for.

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Conflict of interest statement

Competing interests: All authors have completed the Unified Competing Interest form at www.icmje.org/coi_disclosure.pdf (available on request from the corresponding author) and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.

Figures

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Identification of sample of 300 cluster randomised trials (CRTs) included in review
See this image and copyright information in PMC

References

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