A Personalized Normative Feedback Approach to Reducing Heavy Marijuana Use Among College Students in a State with Legalized Adult Recreational Use

Marijuana is a commonly used substance among U.S. college students. Liberalization of marijuana use policies, including legalization of adult recreational use, is hypothesized to decrease injunctive and descriptive norms discouraging use, both of which are protective factors against marijuana misuse. Consequently, social norms represent targets for college student marijuana misuse interventions. This study tested mediated program effects from the Marijuana e-CHECKUP TO GO program, a web-based marijuana misuse intervention providing university-specific personalized normative feedback (PNF) and research-supported protective behavioral strategies (PBS) to students attending a university in a state with legalized adult recreational marijuana. It was hypothesized that direct effects of the Marijuana e-CHECKUP TO GO, adapted for implementation in a state with legalized adult recreational use, would report significantly greater decreases in marijuana use, as measured by a latent factor of daily, weekly, and monthly marijuana use, than participants assigned to a healthy stress management (HSM) comparison condition. Also tested were program effects on descriptive and injunctive norms, and being high during specific student activities (i.e., partying/socializing, being physically active, studying, and during class). Participants were 298 heavy using (approximately 5 times per week) college students (51% male, 19.97 years of age) randomly assigned to either the Marijuana e-CHECKUP TO GO intervention (n =144) or HSM comparison (n = 154) conditions. Structural equation models demonstrated significant decreases in heavy marijuana use for participants in the Marijuana e-CHECKUP TO GO program (p < .01). Comparison of pretest-posttest means demonstrated that differences were due to decreases in use in the intervention group, whereas HSM participants’ pre- and posttest marijuana use means were equivalent. Program effects were also found for decreasing descriptive and injunctive norms, and for reducing use while studying (p < .01). Program effects on norms and using while studying mediated direct program effects. Results demonstrate support for Marijuana e-CHECKUP TO GO and illustrate a specific mechanisms and contexts through which the program had its effects. Results have implications for higher education and public health sectors in that the Marijuana e-CHECKUP TO GO may decrease heavy marijuana use, particularly while college students are studying.