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Ethical Issues Posed by Cluster Randomized Trials in Health Research
Trials (2011)
  • Charles Weijer, The University of Western Ontario
  • Jeremy M. Grimshaw, University of Ottawa
  • Monica Taljaard, University of Ottawa
  • Ariella Binik, The University of Western Ontario
  • Robert Boruch, University of Pennsylvania
  • Jamie C. Brehaut, University of Ottawa
  • Allan Donner, The University of Western Ontario
  • Martin P. Eccles
  • Antonio Gallo, The University of Western Ontario
  • Andrew D. McRae, The University of Western Ontario
  • Raphael Saginur, University of Ottawa
  • Merrick Zwarenstein

The cluster randomized trial (CRT) is used increasingly in knowledge translation research, quality improvement research, community based intervention studies, public health research, and research in developing countries. However, cluster trials raise difficult ethical issues that challenge researchers, research ethics committees, regulators, and sponsors as they seek to fulfill responsibly their respective roles. Our project will provide a systematic analysis of the ethics of cluster trials. Here we have outlined a series of six areas of inquiry that must be addressed if the cluster trial is to be set on a firm ethical foundation: 1. Who is a research subject? 2. From whom, how, and when must informed consent be obtained? 3. Does clinical equipoise apply to CRTs? 4. How do we determine if the benefits outweigh the risks of CRTs? 5. How ought vulnerable groups be protected in CRTs? 6. Who are gatekeepers and what are their responsibilities? Subsequent papers in this series will address each of these areas, clarifying the ethical issues at stake and, where possible, arguing for a preferred solution. Our hope is that these papers will serve as the basis for the creation of international ethical guidelines for the design and conduct of cluster randomized trials.

  • Bioethics,
  • Medical ethics,
  • Cluster randomized trial,
  • Health research
Publication Date
April 20, 2011
Citation Information
Charles Weijer, Jeremy M. Grimshaw, Monica Taljaard, Ariella Binik, et al.. "Ethical Issues Posed by Cluster Randomized Trials in Health Research" Trials Vol. 12 Iss. 100 (2011)
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