The entire fourth grade of boys (ages 9–10 years) and their families from schools with higher incidences of juvenile delinquency in the neighborhood for a medium-sized metropolitan area (Eugene-Springfield in Oregon) were invited to participate in the study. The recruitment rate was 74.4% (N = 206), and retention was at least 97% at each wave through the senior year of high school (Capaldi et al., 1997). The sample size of boys was 203 (99%) in Grade 6 and 201 (98%) in Grade 12 (age 17–18 years). The sample was predominantly Caucasian (90%), with 10% being African-American, Hispanic, Native-American, or mixed race, and 75% lower or working class.
