Competing Theories of Marijuana Use: A Longitudinal Study

Constructive debate over public policy concerning the use and possession of marvuana is hampered by a lack of adequate empirical tests which assess the relative independent predictive power of theories designed to account for maruuana use. This paper presents a longitudinal study of coliege student maruuana use which allows assessment of the relative utility of certain of these theories. Consistent with prior studies, orientation toward a marijuana-using reference group is the most substantial predictor of mariuana use in this study. Contrary to earlier conclusions based solely on cross-sectional data, maruuana use at follow-up is not related to initial lack of commitment to conventional institutions, directly or indirectly, when statistical controls for other theoretical variables are applied. In addition, psychological distress at follow-up is associated with lower levels of initial marijuana use, when other spurious effects are removed. Finally, degree of involvement in conventional activities is not related to marijuana use. The implications for reinterpretation of previous data are discussed.