Editorial: Demystifying the Placebo Effect

Placebo effects are a tantalizing concept that have captured public attention since at least 1955, when Henry Beecher (1) cataloged evidence across 15 large studies (totaln = 1,082 patients) and concluded that 35.5.% (±2.2%) of individuals “respond” to placebo. The results presented by Beecher seem plausible at first read. The goal of placebos in medical research is often described as “to distinguish pharmacological effects from the effects of suggestion … and to obtain an unbiased assessment of the result of experiment” (1, p. 1602). Inherent in this goal is a claim that all medical interventions might have some causal effect that operates via psychological mechanisms and that the strength of such an effect is independent of the mode of intervention (2,3). However, without clearly articulating the nature of this causal effect, we cannot refute or support the existence of this effect.
Source: American Journal of Epidemiology - Category: Epidemiology Source Type: research