"Control subjects" refers to a group of people or things in an experiment that do not receive the treatment or intervention being tested. They are used as a comparison to evaluate the effects of the treatment. Full definition
Most of the studies matched case with control subjects for sex and age. (academic.oup.com)
A 2005 review found that 45 percent of participants who underwent psychotherapy became pregnant compared with only 14 percent of control subjects who received no intervention. (scientificamerican.com)
Adult crime rates were higher in all groups of antisocial girls than in any group of either normal control subjects or girls with other psychiatric problems. (personalityresearch.org)