than did individuals in pairs concordant for low substance risk (the sole exception was a lack of association between alcohol dependence and educational attainment in low risk twins from discordant twin pairs). We observed little change in point estimates after adjustment for depression, conduct disorder, service in Southeast Asia and PTSD, with many effects remaining significant. The exceptions were cannabis dependence for individuals in pairs concordant for high-risk, and cannabis initiation and dependence in the high risk twins from discordant pairs; alcohol dependence remained unassociated with educational attainment in the low-risk individuals from discordant pairs.
