Why is a control group used in research?

A control group is an essential component of research design because it serves as a baseline against which the effects of the experimental treatment can be measured. By having a control group, researchers can compare outcomes between participants who receive the treatment and those who do not. This comparison helps to isolate the specific effects of the intervention being tested, allowing researchers to determine if the observed changes in the experimental group are truly due to the treatment rather than other extraneous factors.

In studies without a control group, it can be difficult to ascertain whether the outcomes would have occurred naturally or as a direct result of the intervention. Thus, the presence of a control group enhances the validity and reliability of the research findings, making it clear what the effect of the treatment is in relation to standard conditions or existing practices.