Process / pipelineexperimental design

Cluster Randomized Trial

A cluster randomized trial (CRT) randomizes intact groups—schools, clinics, villages, or hospital wards—rather than individuals. Developed by Campbell, Grimshaw, and colleagues in the late 1990s to address real-world settings where intervention delivery or contamination occurs at the group level, CRTs are now standard for evaluating population-level, community-based, and policy interventions.

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Sources

  1. Campbell, M. K., Grimshaw, J. M., & Elbourne, D. R. (2000). Intracluster correlation coefficients in cluster randomized trials: empirical insights into how should they be reported. BMC Medical Research Methodology, 4, 30. DOI: 10.1186/1471-2288-4-30
  2. Eldridge, S. M., Ashmore, S., Frenkel, S., Cryer, C., & Underwood, M. (2006). Uncertainty in analyses of safety after cluster randomization. Clinical Trials, 3(2), 152–162. DOI: 10.1191/1740774506cn142oa
  3. Campbell, M. K., Piaggio, G., Elbourne, D. R., & Altman, D. G. (2012). Consort 2010 statement: extension to cluster randomised trials. BMJ, 345, e5661. DOI: 10.1136/bmj.e5661

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Referenced by

ScholarGateCluster Randomized Trial (Cluster Randomized Controlled Trial (CRT)). Retrieved 2026-06-04 from https://scholargate.app/en/clinical-research/cluster-randomized-trial