This study examines the interrelationships and predictors of involvement in delinquent activities and illicit drug use over a nine-year interval, from adolescence (age 15–16) to young adulthood (age 24–25) in a cohort representative of adolescents formerly enrolled in grades 10 and 11 in public secondary schools in New York State (N =1,004). Persistence of illicit drug use in this period of the life-cycle is greater than for delinquency and is higher among men than among women. Convergences and divergences in intrapersonal and interpersonal predictors of drug use and delinquency are analyzed. Adult illicit drug use is much better predicted by adolescent illicit drug use, especially among men. Among women, early drug use predicts later delinquent behavior. However, illicit drug use in the period from adolescence to early adulthood selectively predicts adult participation in one type of delinquent behavior, namely theft, among men and women, but has no effect on interpersonal aggression. Different risk factors in adolescence other than drug use predict continued delinquent involvement among men and women. In particular, depression plays an important role for women and family factors for men. Lifestyle factors subsequent to adolescence, especially failure to enter the conventional roles of adulthood, such as marriage and continuous employment, are important predictors of continued illicit drug use in adulthood but not of delinquency. Delinquency among males and illicit drug use among females appear to be subject to common etiological factors and may play similar roles in the lives of young people. Convergence between the findings and results reported by others are discussed.
Illicit Drug Use and Health: Analysis and Projections of New York City Birth Outcomes Using a Kalman Filter Model