Nonexperimental Designs

Nonexperimental designs are those research designs that lack manipulation of an independent variable and/or control of nuisance variables through random assignment into control or treatment groups. As a result, cause-and-effect relationships cannot be inferred from nonexperimental designs. This entry describes nonexperimental designs, discusses the reasons they are used, and gives recommendations for dealing with confounding variables.

Despite experimental designs typically being considered the gold standard within the context of science, researchers may opt for a nonexperimental design when manipulation of an independent variable and/or random assignment of study participants into groups is not possible, feasible, ethical, or of interest to the researcher. Nonexperimental designs do not allow for causal inferences to be made from relationships observed between variables. This should not, by itself, relegate [Page 1150]nonexperimental ...