Role of perceived access and harm in marijuana use among adolescents

A three-pronged substance abuse prevention intervention was undertaken by a Midwestern, suburban community. Analysis of the long-term impact of the intervention revealed a reduction in alcohol use among students. However, student marijuana use was not impacted as positively. This interdependence between the use of alcohol and marijuana has been reported in the literature, but the role of cognitive factors has not been adequately studied. The current study examined the role of perceived access to alcohol and marijuana and perceived harm associated with alcohol and marijuana use on marijuana use. Data were collected from 11,542 8th--12th grade students in 1998, 2000, and 2003. Data were examined via two sets of logistic regression analyses investigating (1) the role of alcohol use and access to alcohol and marijuana in past month and lifetime marijuana use and (2) the role of alcohol use and perceptions of harm associated with alcohol and marijuana use in past month and lifetime marijuana use. Results revealed that (a) participants indicating no alcohol use were more likely to report past month and lifetime marijuana use, (b) among older students access to marijuana played a role in past month and lifetime marijuana use only when access to alcohol was limited, (c) perceived harm associated with marijuana played a role in lifetime marijuana use only when perceptions of harm associated with alcohol were low.