What is the purpose of a control group in an experiment?

The purpose of a control group in an experiment is to serve as a comparison for the experimental group. By having a control group that does not receive the experimental treatment or intervention, researchers can determine whether any changes observed in the experimental group are due to the treatment itself rather than other external factors. This comparison helps establish a baseline, allowing for the identification of causal relationships between the independent and dependent variables in the study.

For instance, if the experimental group receives a new medication while the control group receives a placebo, any differences in health outcomes can be attributed more confidently to the medication. This element is crucial in scientific research, as it enhances the validity and reliability of the findings, ensuring that the results are not the product of chance or confounding variables.