At T1 and T2, adolescents reported (0 = not true, 1 = somewhat true, 2 = very true or often true) on their hyperactive–inattentive symptoms and conduct problems using the DSM-oriented attention deficit/hyperactivity disorder and conduct problems scales of the youth self report [58]. For T1 hyperactive–inattentive symptoms and conduct problems, α's = 0.83 and 0.83. For T2 hyperactive–inattentive symptoms and conduct problems, α's = 0.80 and 0.77. Note that these measures did not include substance use items. Adolescent reports of T1 symptomatology were predictors of corresponding T2 outcomes for the prospective prediction. Adolescents’ reports were used because they were the only informants who reported on symptoms at two waves, allowing us to test change in symptoms. See Table 1 for descriptive statistics.
