Glossary Term:


control group



In research or clinical trials, the group that does not get the treatment being tested. In cancer research, this group most often gets standard treatment (which has already been tested and is in general use). If no standard treatment exists, the control group may get a placebo or sham treatment. Most cancer clinical trials do not use placebos unless they are given along with an active drug. It’s unethical to give someone a placebo instead of a treatment that’s known to work. Also sometimes called the comparison group.