are depressed. Parental depression itself is among the strongest predictors of depression in offspring (Petersen, Compas, Brooks-Gunn, Stemmler, Ey, and Grant, 1993; see Box 6.3 in Chapter 6). Clinical and education interventions for multiple family members based on etiological studies of resilient adolescents exposed to parental depression have been developed (Beardslee, Salt, Porterfield, Rothberg, van de Velde, Swatling et al., 1993; Beardslee, Hoke, Wheelock, Rothberg, van de Velde, and Swatling, 1992; Beardslee, 1990), and rigorous testing of the effects of these interventions on children's behaviors and psychopathology is currently under way.
Biological events associated with puberty have come to symbolize the transition from childhood to adolescence. This period between childhood and adulthood has become more prolonged as the age of puberty has decreased in industrialized nations (now beginning for girls on average at age 12½ years) and the entry into full-time productive adult roles has been delayed by educational decisions. Hamburg (1992) has described the developmental risk factors that are associated with adolescence, including the exploratory behavior that is central to early adolescence. For example, children today appear to be at greatest risk for the initiation of substance use and delinquent behaviors indicative of conduct disorder from ages 12 to 15.
The early initiation of delinquent behaviors or substance use has been shown to be strongly predictive of antisocial personality or substance abuse disorders. Thus efforts to prevent conduct disorder and substance abuse disorders during adolescence have focused largely on reducing the incidence of disorders by preventing early onset. Even though the co-morbidity of numerous disorders, including substance abuse, conduct, and mood disorders, has been well established (Elliott, Huizinga, and Menard, 1989; Jessor and Jessor, 1977), the preponderance of research on preventive interventions for adolescents has been disorder-specific, focusing for the most part on the prevention of substance abuse, or to a lesser extent, on the prevention of conduct disorder. Virtually no prevention programs during adolescence have focused on the prevention of depressive disorders or depressive symptoms (Muñoz, 1993a) or schizophrenia, in spite of the fact that the incidence of depressive disorders increases during this period (Petersen et al., 1993) and the initial onset of schizophrenia often occurs in late adolescence. Few prevention studies targeting adolescents have measured the effects of intervention on the incidence of multiple disorders.