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PlaceboAudio (En español)

Also known as: Sham, Sugar Pill

An inactive drug (or other intervention) that is identical in appearance to a therapeutically active drug. In some clinical trials, researchers compare the effects of a placebo with those of an active drug under investigation to determine if the active investigational drug is effective.

See Related Term(s):  Placebo Effect, Placebo-Controlled Trial


Placebo EffectAudio (En español)

An effect (usually, but not necessarily, beneficial) that arises from an expectation that the given drug (or other intervention) will have an effect. In a clinical trial, placebo effect can refer to an effect experienced by either a participant or a researcher.

See Related Term(s):  Placebo


Placebo-Controlled TrialAudio (En español)

A type of clinical trial. In placebo-controlled trials, one group of participants (the control arm) receives an inactive drug (or other intervention), called a placebo, while another group of participants (the experimental arm) receives the active drug being tested. The two groups are compared to see if the drug is more effective than the placebo.

See Related Term(s):  Placebo