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 researchers compared people invited to screening between 2008 and 2012 with a control group whose members were either invited later or were not invited at all.

From Science Daily ● Aug. 21, 2026

The participants with severe language impairments performed as well as a control group.

From Science Daily ● Aug. 11, 2026

One group completed interval training once each week, another completed interval training three times each week, and the third served as a control group.

From Science Daily ● Aug. 2, 2026

A three-year study showed it slowed progression by 75% compared to an external control group.

From The Wall Street Journal ● Jun. 19, 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