Placebo-controlled

A placebo-controlled trial is one in which a new medicine is tested against a placebo - a medicine that contains no active ingredients.

In placebo-controlled trials, people are assigned to a group (treatment arm) that receives the medicine, or a group that receives the placebo. This is one way to improve the chances that any benefit experienced by the treatment group receiving the medicine is due to the active ingredient in that medicine rather than some other factor.

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