control group

American  

[kuhn-trohl groop] / kənˈtroʊl ˌgrup /

noun

1. (in an experiment or clinical trial) a group of subjects closely resembling the treatment group in many demographic variables but not receiving the active medication or factor under study and thereby serving as a comparison group when treatment results are evaluated.

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control group British  

noun

1. any group used as a control in a statistical experiment, esp a group of patients who receive either a placebo or a standard drug during an investigation of the effects of another drug on other patients

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Etymology

Origin of control group

First recorded in 1950–55

Compare meaning

How does control-group compare to similar and commonly confused words? Explore the most common comparisons:

• control group vs. experimental group

Example Sentences

See Examples For:

control group

The control group continued using its usual daily eating window of 12 hours or longer.

From Science Daily ● Jul. 18, 2026

The company is leaning toward a trial that compares patients receiving the therapy against a control group receiving standard treatments and a “sham” procedure to rule out any placebo effect.

From Barron's ● Jun. 17, 2026

Among semaglutide users, researchers recorded 794 fractures, compared with 1,045 fractures in the control group.

From Science Daily ● Jun. 16, 2026

As a result, the number of refunds paid to customers due to items being out of stock fell by 2.6% in the treatment group, compared with the control group.

From The Wall Street Journal ● Jun. 9, 2026

According to him, a majority of the cancer victims who’d been prayed for were out whooping it up on the town, while their counterparts in the control group had shriveled up and died.

From "Anthem of a Reluctant Prophet" by Joanne Proulx