Comparing the results of a group receiving treatment with the clinical control group is essential to help rule out imagined or random effects of the treatment.

A clinical control group is a group of individuals, involved in a healthcare experimentation, who do not receive the treatment, in order to determine the effectiveness of the drug, supplement or treatment being tested.

Barkley points out numerous differences emerged in studies between those with ADHD and general population controls and between those with ADHD and Clinical control groups that make such assertions moribund.

True, you can get a bunch of undergraduates to buy and sell a fictitious commodity or bid in a simulated auction; but you can't persuade the International Monetary Fund to rescue only half of the economies in crisis, using the rest as a clinical control group.