Cluster Trials

The CONSORT extension for Cluster Trials was updated in 2012 to be in-line with CONSORT 2010 and is available for download below. 

The main CONSORT Statement provides recommendations for reporting parallel group randomized trials, in which individual participants are randomly assigned to health care interventions. Cluster trials, however, randomize interventions to groups of patients (e.g., families, medical practices) rather than to individual patients. The main issue associated with their design, conduct, analysis, and interpretation, compared with individually randomized trials, is that two different units of measurement—the cluster and the patient—are used. Each needs to be reported carefully.

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Campbell MK, Piaggio G, Elbourne DR, Altman DG; for the CONSORT Group. Consort 2010 statement: extension to cluster randomised trials. BMJ. 2012 Sep 4;345:e5661. PMID: 22951546