control group

[ kuhn-trohl groop ]

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.

control group

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

Word History and Origins

Origin of control group¹

First recorded in 1950–55

Example Sentences

The group with cold toes and high levels of recreational cold exposure had roughly the same ability to detect temperature changes as the control group, and their blood vessels dilated to a similar degree.

From Outside Online

Once again, the control group has plenty of people with seemingly better endurance genes than the endurance Olympians.

From Outside Online

In the original study, the plyometric group improved their running economy by an average of seven percent, the dynamic weight training group improved by four percent, and a control group that didn’t do either saw no change in their running economy.

From Outside Online

In a control group where both mice partners experienced inflammation, the animals’ sensitivity didn’t change after their time together.

From Science News

That said, most of the studies exploring this connection don’t include a control group, or a baseline for comparison.

From Popular-Science

A control group—a population of gorillas unaffected by Ebola, separated by a river and 20 kilometers—was also observed.

From The Daily Beast

The control group proved able to respond two to two and a half times faster than usual and with poor aim.

From The Daily Beast

The researchers examined stories in 469 local papers following suicides in both the clustered and the control group.

From The Daily Beast

In the Oregon study, 5.1 percent of the people in the control group had elevated GH levels.

From The Daily Beast

For one thing, you'd probably have trouble getting people to stay in the control group once you put them there.

From The Daily Beast

There is no control group, and consequently, no way of knowing whether the improvement was due to the removal of the defect.

From Project Gutenberg

As a control group, there were chosen 45 boys who had had no operation, and who lived and worked under the same conditions.

From Project Gutenberg

The average of the boys in the control group was 7421 and for the first group after operation 7406.

From Project Gutenberg

All members of this group were examined,—to the number of fifty-six, and from them the control group was finally selected.

From Project Gutenberg

The average improvement of the test group in excess of the control group is, then, 183 per cent.

From Project Gutenberg