Sex Differences in Self-Report and Behavioral Measures of Disinhibition Predicting Marijuana Use Across Adolescence

Disinhibition has been consistently linked to substance use across development. Recent research suggests, however, that these relations may be influenced by both sex and measurement approach. The current study examined the moderating effect of sex on the association between behavioral and self-report measures of disinhibition and marijuana use across adolescence. Participants were 115 boys and 89 girls initially evaluated at Grade 8 using a laboratory behavioral assessment and self-report questionnaires of disinhibitory variables. Marijuana use was measured annually from Grades 9 through 12. Results suggest that boys and girls did not differ on either self-reported or behaviorally assessed levels of disinhibition, and that disinhibition measured using both approaches was associated with increases in marijuana use over time. There was a significant interaction between sex and disinhibition, suggesting that boys (but not girls) who self-reported elevations in disinhibition evidenced greater increases in marijuana use. The current findings add to a growing literature supporting the importance of using multiple methods to assess disinhibition and highlight the critical role of biological sex in understanding these relations.