The age 14 parental knowledge measure was the sum score of four adolescent self-report items (α = .78) on the degree to which their parents know about their daily plans, activities and whereabouts, how they spend their money, and where/who they are with when not at home (Chassin et al., 1993). Responses were made on a 4-point scale ranging from almost always to rarely or never. Items were reverse scored and summed so higher scores indicate more parental knowledge. The age 14 peer deviance measure was the sum score of four adolescent self-report items regarding the number of friends/acquaintances who drink, smoke, use drugs, and get into trouble at school (α = .77). Responses were made on a four-point scale ranging from none to more than five, and were summed such that higher scores indicate higher peer deviance. For both peer deviance and parental knowledge sum scores were created and adjusted for missingness. Prorated sum scores were calculated for individuals who responded to at least half of the items by scaling up their raw sum score based on the number of missing items.
