Abstract
Growing use of cluster randomized control trials (RCTs) in health care research requires careful attention to study designs, with implications for the development of an evidence base for practice. The objective of this study is to investigate the characteristics, quality, and reporting of cluster RCTs evaluating occupational therapy interventions to inform future research design. An extensive search of cluster RCTs evaluating occupational therapy was conducted in several databases. Fourteen studies met our inclusion criteria; four were protocols. Eleven (79%) justified the use of a cluster RCT and accounted for clustering in the sample size and analysis. All full studies reported the number of clusters randomized, and five reported intercluster correlation coefficients (50%): Protocols had higher compliance. Risk of bias was most evident in unblinding of participants. Statistician involvement was associated with improved trial quality and reporting. Quality of cluster RCTs of occupational therapy interventions is comparable with those from other areas of health research and needs improvement.