double-blind study

double-blind study,

an experiment designed to test the effect of a treatment or substance by using groups of experimental and control subjects in which neither the subjects nor the investigators know which treatment or substance is being administered to which group. In a double-blind test of a new drug, the substance may be identified to the investigators by only a code. The purpose of a double-blind study is to eliminate the risk of prejudgment by the participants, which could distort the results. A double-blind study may be augmented by a cross-over experiment, in which experimental subjects unknowingly become control subjects, and vice versa, at some point in the study. See also placebo.

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double-blind study,

n experimental technique in clinical research in which neither the researcher nor the patient knows whether the treatment administered is considered inactive (placebo) or active (medicinal).

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double-blind study

a study of the effects of a specific agent in which neither the administrator nor the recipient, at the time of administration, knows whether the active or an inert substance is given.