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Is the concept of clinical equipoise still relevant to research?

BMJ 2017; 359 doi: (Published 28 December 2017) Cite this as: BMJ 2017;359:j5787
  1. Spencer Phillips Hey, faculty member1 2,
  2. Alex John London, Clara L West professor of ethics and philosophy3,
  3. Charles Weijer, Canada Research chair in bioethics4,
  4. Annette Rid, reader in bioethics and society5,
  5. Franklin Miller, professor of medical ethics in medicine6
  1. 1Harvard Center for Bioethics, Boston, MA, USA
  2. 2Program on Regulation, Therapeutics, and Law, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
  3. 3Center for Ethics and Policy, Carnegie Mellon University, Pittsburgh, PA, USA
  4. 4Departments of Philosophy and Medicine, University of Western Ontario, London, ON, Canada
  5. 5Department of Global Health and Social Medicine, King’s College London, London, UK
  6. 6Medical Ethics in Medicine, Weill Cornell Medical College, New York, USA
  1. Correspondence to: S P Hey shey{at}, A Rid annette.rid{at}

Spencer Hey, Alex John London, and Charles Weijer argue that there is no better framework for justifying patient participation in research. But Annette Rid and Franklin Miller say that it is a mistake to require clinical research ethics to align with the norms of clinical practice

Yes—Spencer Phillips Hey, Alex John London, Charles Weijer

Whether they are in their doctor’s clinic or participating in a randomised controlled trial, patients have an interest in receiving competent medical care. Doctors also have a duty to provide patients with care consistent with professional standards. However, in a randomised trial a patient’s interests and the doctor’s duty seem to conflict with the scientific goals of the trial. How can it be in the patient’s interest to leave the choice of therapy to chance? How can randomisation comport with the physician’s duty of care?

Clinical equipoise was first proposed as a solution to the problem of randomisation 30 years ago. It is defined as a state of disagreement or uncertainty in the informed, expert medical community about the relative clinical merits of the intervention arms in a trial.1 This state of equipoise may mean that there is insufficient evidence to warrant a judgment that one intervention in the trial is inferior to the others. It may also mean that some experts favour one intervention over the others, but different experts prefer different interventions for the same patients.2 However, so long as one or both of these conditions apply to a trial, each of its arms is broadly consistent with competent medical care. This means that a patient can enrol in the trial without having to worry about being disadvantaged and a physician can refer patients without violating the duty of care.3

Scientific and social value

But equipoise does more than simply solve the problem of randomisation. It can …

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