Longitudinal Links between Identity and Substance Use in Adolescence

Abstract

Identity development has been linked to substance use, however, the directionality of this relationship remains unclear. We examined the longitudinal associations of educational and relational identity with substance use across three annual waves in 360 Dutch adolescents (Mean age = 13.7 years). Using the identity dimensions of commitment, exploration, and reconsideration as indicators, we found three latent profiles clusters: achievement, diffusion, and moratorium. With latent profile transition analysis, we examined substance use as a predictor of profile transition. Using classification probabilities to determine participants’ clusters at each time point, we distinguished three identity transition groups (stable, progressive, and regressive). These groups were used to examine the effects of identity transition group membership on substance use with ANCOVAs. No longitudinal associations were found in either direction, but we found significant cross-sectional correlations between identity and substance use. Therefore, our findings do not support a directional process linking identity and substance use. Instead, these associations suggest a spectrum/continuity or common cause model.