Any study which compares two groups by virtue of different therapies or exposures fulfills this definition.
a very effective means to demonstrate the efficacy of therapies compared to placebo
A clinical study that includes a comparison (control) group. The comparison group receives a placebo, another treatment, or no treatment at all.
A clinical trial in which one or more groups receive an experimental intervention and another group acts as the control (or comparison) group.
is a study that uses the same design features of a randomised controlled clinical trial, but, for reasons beyond the control of the investigators, the subjects are assigned using a non-random process into control or experimental groups.