Risk Factors for Driving After and During Marijuana Use

Objective: Use of marijuana before or while driving significantly contributes to driving impairment and elevated risk of motor vehicle accidents; however, this risk behavior is common among users. Little is known about the etiology of driving while under the influence of marijuana. Method: Guided by social learning theory, this study examined marijuana outcome expectancies and other driving related cognitions as predictors of the frequency of driving after smoking marijuana (DASM) and smoking marijuana while driving (SMWD). A community sample of 151 (64% male) non treatment-seeking frequent marijuana users completed questionnaires on variables of interest. Results: Perceived driving-related peer norms (i.e., perception that fewer friends disapprove of DASM and SMWD and of riding with a driver under the influence of marijuana) were associated with lower frequency of both DASM and SMWD. Perceived dangerousness of DASM was also associated with decreased frequency of DASM. Conclusions: Our findings suggest a range of potentially important targets for interventions intended to reduce the likelihood and frequency of driving while under the influence of marijuana.