Interaction

In most research contexts in the biopsychosocial sciences, researchers are interested in examining the influence of two or more predictor variables on an outcome. For example, researchers might be interested in examining the influence of stress levels and social support on anxiety among first-semester graduate students. In the current example, there are two predictor variables—stress levels and social support—and one outcome variable—anxiety. In its simplest form, a statistical interaction is present when the association between a predictor and an outcome varies significantly as a function of a second predictor. Given the current example, one might hypothesize that the association between stress and anxiety varies significantly as a function of social support. More specifically, one might hypothesize that there is no association between stress and anxiety ...