Double Blind Definition

dub'lblīnd

noun

A testing procedure designed to avoid biased results by ensuring that at the time of the test neither the administrators nor the subjects know which subjects are receiving a test treatment and which belong to a control group.

American Heritage Medicine

adjective

Designating or of a technique used to test objectively the effects of a drug, course of treatment, etc. in which neither the subjects nor the researchers know during the testing who is actually receiving the drug, treatment, etc. and who is not, as in an experiment involving a drug and a placebo.

Webster's New World

Describing an experiment (usually medical) in which the identity of those conducting the test(s) is kept secret from both the subjects and the administrators until the outcome of the experiment is known.

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