Placebo Effect

In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan.


Placebos have been used in medicine since antiquity and may have been significant in improving health and quality of life when little was known about the etiology of most illnesses. Most outcomes were likely due to a placebo effect since the available treatments were unproven or have since been proven invalid. For example, snake oil and bloodletting was a common practice in the past; however, those who responded positively to those treatments likely did so because of a placebo effect. The emergence of placebo-controlled clinical trials in the 1940s reintroduced the placebo effect to the modern day. The classic article "The Powerful Placebo" by Henry Beecher highlighted the placebo effect and emphasized a need to account for it to evaluate the efficacy of a treatment modality properly. Both research and clinical settings utilize the placebo effect.

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