Does substance use moderate the effects of parents and peers on risky sexual behaviour?

We investigated the moderating effects of drug/alcohol use in the past 3 months on the relationships of peer influence, parental permissiveness, and teen disposition (i.e., achievement motivation, attitude toward school, and value placed on health) with adolescent risky sexual behaviour. Participants were 207 adolescents receiving psychiatric care. Substance use did not moderate the relationship between adolescent disposition and risky sex. By contrast, peer influence and parental permissiveness were linked to risky sex but only for teens who reported using drugs/alcohol. Controlling for other predictors in the model, negative peer influence explained 21% and parental permissiveness explained 13% of the variance in risky sex among substance users, but less than half of 1% of the variance among non-substance users. The disinhibiting effects of substance use on decision-making and the need for effective parental monitoring to reduce opportunities for risk behaviour are discussed.