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Internal and external validity of cluster randomised trials: systematic review of recent trials

Sandra Eldridge1, Deborah Ashby, Catherine Bennett

  • 1Centre for Health Sciences, Barts and The London School of Medicine and Dentistry, London E1 2AT. s.eldridge@qmul.ac.uk

BMJ (Clinical Research Ed.)
|March 28, 2008
PubMed
Abstract

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