Clinical Equipoise - History

History

Shaw and Chalmers argued early on that "If the clinician knows, or has good reason to believe, that a new therapy (A) is better than another therapy (B), he cannot participate in a comparative trial of Therapy A versus Therapy B. Ethically, the clinician is obligated to give Therapy A to each new patient with a need for one of these therapies." Researchers would thus face an ethical dilemma if they wanted to continue the study and collect more evidence, but had compelling evidence that one of the tested therapies was superior. They further stated that any results should be withheld from the researchers during the trial until completion to avoid this ethical dilemma and ensure the study’s completion.

This method proved to be difficult in modern research, where many clinical trials have to be performed and analyzed by experts in that field. Freedman proposed a different approach to this ethical dilemma called clinical equipoise. Clinical equipoise occurs "if there is genuine uncertainty within the expert medical community — not necessarily on the part of the individual investigator — about the preferred treatment." Clinical equipoise is distinguished from theoretical equipoise, which requires evidence on behalf of the alternative treatments to be exactly balanced and thus yields a very fragile epistemic threshold for favoring one treatment over the other. Theoretical equipoise could be disturbed, for example, by something as simple as anecdotal evidence or a hunch on the part of the investigator. Clinical equipoise allows investigators to continue a trial until they have enough statistical evidence to convince other experts of the validity of their results, without a loss of ethical integrity on the part of the investigators.

Equipoise is also an important consideration in the design of a trial from a patient’s perspective. This is especially true in randomized controlled trials (RCTs) for surgical interventions, where both trial and control arms are likely to have their own associated risks and hoped for benefits. The condition of the patient is also a factor in these risks. Ensuring that trials meet the standards of clinical equipoise is an important part of patient recruitment in this regard; it is likely that past trials that did not meet conditions of clinical equipoise suffered from poor recruitment.