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

Reduced hair volume or density was also substantially more common, affecting 42% of users versus 19% of the control group.

From Science Daily ● Oct. 12, 2026

He noted that it wasn’t compared to a control group and it’s difficult to tell what contributed to changes.

From The Wall Street Journal ● Sep. 25, 2026

Admittedly, my professional history makes me a poor control group.

From Salon ● Sep. 23, 2026

There were no differences from the control group in the other areas.

From The Wall Street Journal ● Sep. 18, 2026

Continuing her sentence, Rachael said, “Uncle Eldon should have an android group and a control group set up by now. So let’s go.”

From "Do Androids Dream of Electric Sheep?" by Philip K. Dick