Clinical equipoise and risk-benefit assessment.

Clinical equipoise is widely regarded as an ethical requirement for the design and conduct of randomized controlled trials (RCTs). Underlying clinical equipoise is the norm that no patient should be randomized to treatment known (or believed by the expert clinical community) to be inferior to the established standard of care. This implies that patient-subjects should not be exposed to net risks in control groups of randomized trials - risks that are not compensated by the prospect of direct medical benefits from the control intervention. However, proponents of clinical equipoise have no moral objections to permitting net risks for 'nontherapeutic' research procedures employed in clinical trials. This differential assessment makes risk-benefit assessment of randomized trials incoherent. In this article, I examine critically four arguments in defense of clinical equipoise as a requirement for risk-benefit assessment. Each of these arguments fails to support clinical equipoise, leading to the conclusion that we should dispense with this principle in risk-benefit assessment of RCTs.