The nested boxes on the left side of the figure illustrate the multiple-gating screening procedure (Lochman, 1995) applied to kindergarteners in the 54 schools (N=9,594). First, teacher ratings of disruptive behavior using the Teacher Observation of Classroom Adaptation-Revised (TOCA-R) Authority Acceptance score (Werthamer-Larsson, Kellam, & Wheeler, 1991) were used to identify children scoring in the highest 40 percent within cohort and site (n=3,274). These children were further screened using parent-ratings on the Aggression scales of the Child Behavior Checklist (Achenbach, 1991). Teacher and parent scores were standardized within site and summed to yield a severity-of-risk screen score. Children were ranked on this risk score, and selected into the study in order from highest risk to lowest until desired sample sizes were reached within sites, cohorts, and conditions (979 children [10 percent of total] solicited; 891 participants—intervention n=445, control n=446—enrolled). The sample was 61 percent male, 47 percent European-American, 51 percent African-American, and 2 percent of other ethnicity. Mean age was 6.58 years (SD = 0.48) at enrollment in the first grade. During the elementary school phase (grades 1 to 5),
