Perceived local enforcement, personal beliefs,and underage drinking: an assessment of moderating and main effects.

OBJECTIVE Strategies to enforce underage drinking laws are aimed at reducing youth access to alcohol from commercial and social sources and deterring its possession and use. However, the processes through which enforcement strategies may affect underage drinking are not well understood. This study examined three possible processes by which perceived enforcement of underage drinking laws and personal beliefs (perceived alcohol availability, perceived harm, and personal disapproval of alcohol use) may influence alcohol use among adolescents. METHOD Survey data were obtained from 20,747 adolescents (48.3% males) in 115 school districts who participated in the 2006 Oregon Healthy Teens survey. Linear regression analyses were conducted to examine possible interactive and main effects of perceived enforcement and personal beliefs on past-30-day alcohol use. Analyses were adjusted for clustering of observations within school districts and included student demographics and age of alcohol use initiation as covariates. RESULTS Statistically significant interaction effects on past-30-day alcohol use were found for perceived police enforcement and the three personal beliefs variables, indicating weaker associations between personal beliefs and past-30-day alcohol use at higher levels of perceived enforcement. Main effects of perceived enforcement and personal beliefs variables were also observed in the presence of interaction effects. CONCLUSIONS Evidence for a moderating effect of perceived local enforcement on the relationships between personal beliefs and drinking behaviors suggests that the combination of individually focused prevention programs and local enforcement of underage drinking laws may have the greatest impact on underage drinking.