"The onset of illicit substance use during adolescence ... likely started as a trickle in early childhood. Understanding antecedent factors and how they grow ... leads to adolescent drug use is important for theories of social development as well as policy formulations to prevent onset ... A dynamic cascade model of the development of adolescent substance-use onset ... was tested with a longitudinal sample of 585 boys and girls from the Child Development Project, who were followed from prekindergarten through grade 12."--P. vii.