Why Sackett's analysis of randomized controlled trials fails, but needn't

Sackett and others3 take the view that a physician must be substantially uncertain about the merits of a treatment to ethically recommend enrolment for a patient. We do not contest the physician's obligation to serve the best interests of each patient; comorbidity or other reasons might make enrolment in one or both of the trial arms undesirable for any particular patient. However, fulfilling that obligation requires not only clinical skill and an understanding of each patient's situation, but up-to-date knowledge of the best therapeutic strategies available. Physicians cannot develop this knowledge in isolation, but must rely on the collective judgement of the medical community as a whole. The uncertainty or certainty of any individual physician about the relative merits of a treatment is irrelevant to the moral basis of a trial. Rather, the ethical basis for a clinical trial arises from the uncertainty that rests with the expert clinical community as a whole: this is the state of clinical equipoise described by Freedman.4 Consider a situation in which there was no individual physician uncertainty, with half the physicians considering treatment A preferable, and half preferring B. A consequence of Sackett's position would be that a randomized trial could not move forward: physicians could not, in good conscience, enrol any patients. Yet it is just this state of (un)certainty that calls out for evidence as to which is the better treatment. It is important for the individual physician to set aside his or her opinion, bias or "certainty" in deference to the reasoned uncertainty that exists within the larger community of experts. Giving undue weight to a physician's possibly uninformed views, as the uncertainty principle allows, is not consistent with an evidence-based approach to health care. The collective judgement of the medical community relies on the informed views of its members as a whole. Sackett's analysis takes into account the individual physician, but fails to locate that individual within the larger community of which he or she is a part. He briefly considers a group version of the uncertainty principle. However, this seems to be a bit like trying to reinvent the (clinical equipoise) wheel.