Which psychosocial factors moderate or directly affect substance use among inner-city adolescents?

Past etiology of adolescent substance use research concentrated on the main effects of various risk factors. The purpose of this study was to also longitudinally predict interactions on poly-drug use intensity and future smoking among inner-city adolescents. A panel sample of baseline, 1-year and 2-year follow-ups (N = 1459) from the control group of a longitudinal smoking prevention trial participated. We focused on the main effects, as well as, interaction effects between psychosocial protective factors and various risk factors, including perceived norms of friends, peers and adults to use drugs. Significant effects were identified for intensity of poly-drug use and future smoking. The analysis of the poly-drug use outcome indicated that refusal assertiveness undermined perceived friends' drug use and siblings' smoking, and that low risk-taking undermined perceived friends' drug use. There was a main effect for low psychological wellness. The significant interactions between perceived friends' drug use with refusal assertiveness and decision-making skills were observed for future smoking. Moreover, perceived peer smoking norms, siblings' smoking, and high risk-taking also showed significant main effects for increasing future smoking.