control group

American

[kuhn-trohl groop] / kənˈtroʊl ˌgrup /

noun

(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.

control group British

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

To conduct the experiment, adult rats were separated into two groups: a control group and a group that received omeprazole.

From Science Daily

Compared with a control group that also reduced calories but did not eat oats, those on the oat based plan saw a markedly greater improvement in their cholesterol levels.

From Science Daily

The control group also reduced calories but did not consume oats.

From Science Daily

In the two day oat based study, 17 participants in the oat group and 15 in the control group completed the trial.

From Science Daily

Two individuals in the control group withdrew for personal reasons.

From Science Daily

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023