Design and Analysis of Cluster Randomization Trials in Health Research

A cluster randomization trail is one in which intact social units, or clusters of individuals, are randomized to different intervention groups. Trials randomizing clusters have become particularly widespread in the evaluation of non-therapeutic interventions, including lifestyle modification, educational programs and innovations in the provision of health care. The units of randomization in such studies are diverse, ranging from relatively small clusters such as families or households, to entire neighborhoods or communities, but also encompassing workplaces, hospital wards, classrooms and medical practices. The increasing popularity of this design among health researchers over the past two decades has led to an extensive body of methodology on the subject. This book is the first to present a systematic and unified treatment of this topic; it contains distinctive chapters on the history of cluster randomized trials, ethical issues, meta-analysis and guidelines. Written by two of the leading authorities in the field, this book is an essential reference text for investigators in the planning or analysis stages of a study. It is also highly suitable for use as a textbook in a graduate-level course in research methodology, and is aimed at biostatisticians, epidemiologists, health service researchers and public health professionals.

Allan Donner is Professor and Chair of the Department of Epidemiology and Biostatistics, University of Western Ontario, Canada.

Neil Klar is Senior Biostatician in the Division of Preventive Oncology, Cancer Care Ontario, Canada.