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A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition
Published on: September 20, 2019
Cluster randomized controlled trials
Suezann Puffer1, David J Torgerson, Judith Watson
1York Trials Unit, Department of Health Sciences, University of York, York, UK.
Abstract:
Cluster randomized controlled trial (RCT), in which groups or clusters of individuals rather than individuals themselves are randomized, are increasingly common. Indeed, for the evaluation of certain types of intervention (such as those used in health promotion and educational interventions) a cluster randomized trial is virtually the only valid approach. However, cluster trials are generally more difficult to design and execute than individually randomized studies, and some design features of a cluster trial may make it particularly vulnerable to a range of threats that can introduce bias. In this paper we discuss the issues that can lead to bias in cluster randomized trials and conclude with some suggestions for avoiding these problems.
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