Relationship between locus of control and alcohol and drug-related behaviors in teenagers

Seventh, ninth, tenth and twelfth graders, classified as internal or external according to Rotter's Locus of Control Scale, indicated whether or not and why they engaged in alcohol consumption or marijuana smoking behaviors. Overall, a higher proportion of externals than internals drank but the two groups did not generally differ in marijuana smoking behaviors, both findings unsupportive of the "control by addiction" hypothesis. Developmentally different trends among internals and externals for the two types of behaviors suggested an interactive effect between peer culture influences and the locus of control variable. Both groups were otherwise generally similar in their reasons for engaging in the behaviors, in their desire not to stop, and in their increased opinions of themselves.