This study examined the combined influence of two predicting factors—low self-control and commitment to schooling—that research has shown have independent effects on substance abuse. In a sample of 598 college students, this study tested the interactive effects of these factors while controlling for other established predictors of binge drinking and drug use. Analysis showed that participants who had both low self-control and low schooling commitment had significantly higher scores on substance abuse than would be expected from the independent influences of the component factors, which suggests that the combined effects of these predictors on substance abuse have a greater influence than their direct influences.
