Abstract
BackgroundPrevious reviews of cluster randomised trials have been critical of the quality of the trials reviewed, but none has explored determinants of the quality of these trials in a specific field over an extended period of time. Recent work suggests that correct conduct and reporting of these trials may require more than published guidelines. In this review, our aim was to assess the quality of cluster randomised trials conducted in residential facilities for older people, and to determine whether (1) statistician involvement in the trial and (2) strength of journal endorsement of the Consolidated Standards of Reporting Trials (CONSORT) statement influence quality.MethodsWe systematically identified trials randomising residential facilities for older people, or parts thereof, without language restrictions, up to the end of 2010, using National Library of Medicine (Medline) via PubMed and hand-searching. We based quality assessment criteria largely on the extended CONSORT statement for cluster randomised trials. We assessed statistician involvement based on statistician co-authorship, and strength of journal endorsement of the CONSORT statement from journal websites.Results73 trials met our inclusion criteria. Of these, 20 (27%) reported accounting for clustering in sample size calculations and 54 (74%) in the analyses. In 29 trials (40%), methods used to identify/recruit participants were judged by us to have potentially caused bias or reporting was unclear to reach a conclusion. Some elements of quality improved over time but this appeared not to be related to the publication of the extended CONSORT statement for these trials. Trials with statistician/epidemiologist co-authors were more likely to account for clustering in sample size calculations (unadjusted odds ratio 5.4, 95% confidence interval 1.1 to 26.0) and analyses (unadjusted OR 3.2, 1.2 to 8.5). Journal endorsement of the CONSORT statement was not associated with trial quality.ConclusionsDespite international attempts to improve methods in cluster randomised trials, important quality limitations remain amongst these trials in residential facilities. Statistician involvement on trial teams may be more effective in promoting quality than further journal endorsement of the CONSORT statement. Funding bodies and journals should promote statistician involvement and co-authorship in addition to adherence to CONSORT guidelines.
Highlights
Previous reviews of cluster randomised trials have been critical of the quality of the trials reviewed, but none has explored determinants of the quality of these trials in a specific field over an extended period of time
To explore reasons for variation in quality we present these percentages by whether the trial was published in 2004 or earlier, or after 2004; by whether the trial had statistician involvement or not; and for those trials published after 2004, by the strength of the journal’s endorsement of the Consolidated Standards of Reporting Trials (CONSORT) statement
We identified 308 published reports via our electronic search, rejecting 248 on the basis of titles or abstracts (56 non-randomised studies, 68 individually randomised trials, 95 cluster randomised trials either not in residential facilities for older people or in such facilities but randomising units other than the facility or a part of a facility, 21 protocols and other reports with no results, seven pilot or feasibility studies, one cost-effectiveness study)
Summary
Previous reviews of cluster randomised trials have been critical of the quality of the trials reviewed, but none has explored determinants of the quality of these trials in a specific field over an extended period of time. Sample size calculations and analyses should be adjusted to allow for homogeneity of individuals in the clusters, and investigators must avoid potential bias when identifying and recruiting individual participants [1,2,3,4] Previous reviews of these trials indicate low quality in respect of these and other methodological and reporting criteria [4,5,6,7,8,9,10,11,12], and a possible trend from comparing review results of quality improvement over time [4]. Previous research has identified better reporting amongst randomised controlled trials published in journals more strongly promoting the 1996 original CONSORT statement [16]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
