a comparison group in a scientific experiment (e.g., a clinical drug trial) that is used to verify experimental results. A control group is not subject to the intervention under (e.g., not given a drug) so that those receiving the intervention and those not receiving it may be compared. Contrast with treatment arm.
CONTROL ARM
Meaning of CONTROL ARM in English
AIDS English Glossary. Английский словарь СПИДа. 2012