Early onset, prevalence, and predictors of substance use – tobacco, alcohol-drinking, alcohol-drunkenness, and drugs – were studied in 13 and 14-year-old boys and girls in Sweden.

Methods: Self-reported data in four communities were used (n = 1,716). A large set of psychological and social factors were tried as predictors of early onset use (n = 1,459).

Results: There were few gender differences and low prevalence. Primary predictor for early onset in tobacco use was availability; perceived parental approval for alcohol use, and delinquent behaviors for alcohol-drunkenness and drug use.

Conclusions: Individual behavioral factors and parental norms seem to be most important in this age.