Fig. 1.

Theoretical model of attention deficit/hyperactivity disorder (ADHD) as a predictor of substance use (SU), controlling for conduct disorder (CD) and sensation seeking (SS). Thick lines indicate the direct paths c from ADHD at baseline to SU at 5-year follow-up and c′ from ADHD to SU controlled for CD and SS (noted as ADHD → SU w/CD & SS; “w/” = “with”), path b₁ from CD to SU controlled for ADHD and SS, and path b₂ from SS to SU controlled for ADHD and CD. Dotted lines indicate partial correlations of predictors: r_a1 of ADHD with CD (w/SS), r_a2 of ADHD with SS (w/CD), and r_a3 of CD with SS (w/ADHD).