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placebo effect

A placebo effect happens when a patient feels better after taking fake medicine, or when they believe they're taking medicine although they really aren't.

Scientific studies have shown that people often have a positive reaction (both physical and mental) when they think they're taking a drug or receiving a treatment — even if they're not. This placebo effect has to be accounted for in medical studies, so that researchers know a drug is really working. Often one group is given the substance being studied, and the other takes a placebo. Placebo means "I shall please" in Latin.

Definitions of placebo effect
  1. noun
    any effect that seems to be a consequence of administering a placebo; the change is usually beneficial and is assumed result from the person's faith in the treatment or preconceptions about what the experimental drug was supposed to do; pharmacologists were the first to talk about placebo effects but now the idea has been generalized to many situations having nothing to do with drugs
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    type of:
    consequence, effect, event, issue, outcome, result, upshot
    a phenomenon that follows and is caused by some previous phenomenon
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