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Sample size calculations for cluster randomised controlled trials with a fixed number of clusters

Karla Hemming1, Alan J Girling, Alice J Sitch

  • 1Department of Public Health, Epidemiology and Biostatistics, University of Birmingham, UK. k.hemming@bham.ac.uk

BMC Medical Research Methodology
|July 2, 2011
PubMed
Summary

Sample size calculations for cluster randomised controlled trials (CRCTs) with a fixed number of clusters are essential. If the number of clusters is insufficient, the study may not be feasible, impacting detectable differences and power.

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