Structured and Unstructured Activities and Alcohol and Marijuana Use in Middle School: The Role of Availability and Engagement.

Background: Behavioral Theories of Choice applied to substance use suggests that use depends on availability of substances and alternative activities. Applying this theory to younger adolescents offers the possibility of investigating potentially malleable prevention and intervention targets. Objectives: The current study examines the role of perceived availability and engagement in structured and unstructured activities on adolescent alcohol and marijuana use controlling for substance availability. Methods: Data were collected as part of a longitudinal study of 6th-8th graders (N = 1023; 52% female; 76% White; Mage = 12.23 years). Multiple logistic regressions analyzed the impact of availability and engagement in structured and unstructured activities at Wave 1 on heavy drinking and marijuana use by study end in both unadjusted and adjusted models. Results: Availability of unstructured activities was associated with increased likelihood of both marijuana use (b* = .06, p = .04) and heavy drinking (OR = 1.20, p < .001), while availability of structured activities was not significantly associated with likelihood of either marijuana use (b* = -.10, p = .07) or heavy drinking (OR = 0.86, p = .16). Engagement in unstructured activities was significantly associated with increased likelihood of both marijuana use (b* = .06, p = .03) and heavy drinking (OR = 1.11, p = .003), while engagement in structured activities was significantly associated with decreased likelihood of both marijuana use (b* = -.25, p < .001) and heavy drinking (OR = 0.85, p = .046). Conclusions: Perceived availability of and engagement in unstructured activities may present a risk, while perceived availability of and engagement in structured activities may serve as a protective factor for youth substance use.