The leading ethical position on placebo-controlled clinical trials is that whenever proven effective treatment exists for a given condition, it is unethical to test a new treatment for that condition against placebo. Invoking the principle of clinical equipoise, opponents of placebo-controlled trials in the face of proven effective treatment argue that they (1) violate the therapeutic obligation of physicians to offer optimal medical care and (2) lack both scientific and clinical merit. We contend that both of these arguments are mistaken. (...) Clinical equipoise provides erroneous ethical guidance in the case of placebo-controlled trials, because it ignores the ethically relevant distinction between clinical trials and treatment in the context of clinical medicine and the methodological limitations of active-controlled trials. Placebo controls are ethically justifiable when they are supported by sound methodological considerations and their use does not expose research participants to excessive risks of harm. (shrink)

The use of statistics in medical research has been compared to a religion: it has its high priests, supplicants, and orthodoxy. Although the comparison may be more unfair to religion than to research, a useful lesson can nonetheless be drawn: the practice of clinical research may benefit—as does the spirit—from critical self-examination. Arguably, no aspect of the conduct of clinical trials is currently more controversial—and thus in as dire need of critical examination—than the use of placebo controls. The ethical and (...) scientific controversies associated with placebo-controlled trials, never far below the surface, have once again seized public attention. Clearly, concern about these issues within the professional community runs deep and wide, as evidenced by the volume of response generated by Kenneth Rothman and Karin Michels's recent Critique. Criticisms of the use of placebo controls in clinical research are scattered through the literatureo; our objective is to present the case against placebos in a compendious form that takes account of scientific and statistical as well as normative issues. (shrink)