Encyclopedia of Global Bioethics

Living Edition
| Editors: Henk ten Have

Clinical Equipoise

Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-05544-2_84-1


Clinical equipoise is a core concept in the ethics of research involving human participants. It is an ethical precondition for the permissibility of enrolling patients in a randomized controlled trial (RCT). According to Freedman, a state of clinical equipoise obtains when there exists “an honest, professional disagreement among expert clinicians about the preferred treatment” (Freedman, New England Journal of Medicine, 317(3), 144, 1987). Historically, the concept evolved in response to the question: how can a physician, consistent with the duty of care to the patient, offer her enrollment in a randomized controlled trial? Clinical equipoise addresses this ethical difficulty, in part, through the recognition that a physician’s judgment is drawn from, and constrained by, the realm of professional knowledge. When there is disagreement in the professional community as to the preferred treatment, random allocation to one or other treatment in an RCT is consistent with the physician’s duty of care to the patient.


Clinical equipoise Research ethics Randomized controlled trial Duty of care Benefit-harm analysis 
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Further Readings

  1. Weijer, C., Miller, P. B., & Graham, M. (2015). Duty of care and equipoise. In J. D. Arras, E. Fenton, & R. Kukla (Eds.), The Routledge companion to bioethics (pp. 200–214). New York: Routledge.Google Scholar

Authors and Affiliations

  1. 1.Rotman Institute of PhilosophyWestern UniversityLondonCanada