Sage Research Methods – The SAGE Encyclopedia of Communication Research Methods
Control groups are an important aspect of true experimental designs. The presence of control groups allows researchers to confirm that study results are due to the manipulation of independent variables (IVs) rather than extraneous variables. Specifically, control groups comprise participants who are not exposed to the manipulated IV but are measured on the study’s dependent variables (DVs). The extent to which an IV is found to cause the DV is calculated by comparing the differences in the DV observed between the control group and one or more experimental groups. It is important to note that control groups are not present in quasi-experimental designs, which instead compare preexisting characteristics within participants and do not involve experimental manipulation of the IV. This entry covers types …