Reining in the Placebo Effect

What is known as the "placebo effect" has received increasing attention in recent years in scientific investigation and the news media. The concept of the placebo effect, however, is subject to confusion and misleading implications, especially when applied broadly. This essay argues that it is desirable to confine the concept, as applied to biomedicine, to the therapeutic effects of deliberate placebo interventions. The author examines in detail the conceptual problems in characterizing the therapeutic benefits that flow from communication in the clinician-patient relationship as placebo effects.