The early emergence and developmental implications of externalizing behavior problems in toddlers and preschoolers are discussed with an emphasis on which young children are truly at risk for continuing problems. The extant literature is reviewed with a focus on the stability of early externalizing behavior and the diverse pathways that young children, primarily boys, with early-emerging problems may follow. Findings from a number of studies, both epidemiological and high risk, suggest that the small subgroup of boys with multiple risk factors that include especially high levels of early hyperactivity and aggression, and high levels of negative parenting and family stress, are most likely to evidence continuing problems at school entry. Sociodemographic and neighborhood influences are also discussed, as are implications for future research and policy.

Seven hundred thirty-one income-eligible families in 3 geographical regions who were enrolled in a national food supplement program were screened and randomized to a brief family intervention. At child ages 2 and 3, the intervention group caregivers were offered the Family Check-Up and linked parenting support services. Latent growth models on caregiver reports at child ages 2, 3, and 4 revealed decreased behavior problems when compared with the control group. Intervention effects occurred predominantly among families reporting high levels of problem behavior at child age 2. Families in the intervention condition improved on direct observation measures of caregivers' positive behavior support at child ages 2 and 3; improvements in positive behavior support mediated improvements in children's early problem behavior.Problem behavior in middle childhood and adolescence is a predictable outgrowth of problematic adjustment in early childhood (Brook, Whiteman, Cohen, & Tanaka, 1992;Brook, Whiteman, Gordon, & Cohen, 1986;Campbell, Shaw, & Gilliom, 2000;Caspi, Moffitt, Newman, & Silva, 1998;Hawkins, Lishner, Catalano, & Howard, 1986; Lyons-Ruth, Zeanah, & Benoit, 1996;Shaw, Gilliom, Ingoldsby, & Nagin, 2003;Vicary & Lerner, 1983). Longitudinal studies begun with children as young as age 3 years (e.g., Caspi et al., 1998) have revealed an association between early behavior problems and long-term profiles of risk, including substance dependence in young adulthood.Our study was motivated by three principles: (a) the prevention of problem behavior in children and adolescents must be family centered and ecologically focused; (b) for the most effective long-term impact on health, empirically supported family interventions must be brief and Correspondence concerning this article should be addressed to Thomas J. Dishion, Child and Family Center, Department of Psychology, University of Oregon, 195 W. 12th Avenue, Eugene, OR 97401. Electronic mail may be sent to E-mail: dishion@uoregon.edu.. NIH Public Access NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript therefore more cost effective and must be embedded in existing service systems (Hoagwood & Koretz, 1996); and (c) developmental transition points such as toddlerhood, school entry, and early adolescence offer unique opportunities for health promotion and risk reduction because child and family behaviors reorganize at these points (Dishion & Stormshak, 2007;Sameroff & Fiese, 1987).Intervening during the first of these transition points, when the child begins to walk and becomes physically autonomous (ages 1 − 2 years), is an important strategy for preventing adolescent problem behaviors such as delinquency and substance use. Parent -child interaction patterns during this transitional developmental period are challenged by normative increases in child mobility, language, independence, and physical aggression and noncompliance. Families' adaptation to this developmental transition forms the basis for subsequent developmental stages (Shaw, Bell, ...

A developing body of research suggests that there are few sex differences in the rate and severity of problem behavior in early childhood, but clear sex differences emerge at about 4 years of age. The authors explore 2 hypotheses to further the understanding of emerging sex differences in problem behavior across the first 5 years of life. The first posits that the change in girls' problem behavior from infancy to school entry represents a channeling of early problem behavior into predominantly internalizing problems as a result of socialization. The second hypothesis is that the change in girls' early problem behavior during the preschool period results from the more rapid biological, cognitive, and social-emotional development of girls relative to boys. The authors review research on the influence of parents, teachers, and peers on girls' behavior from infancy to preschool regarding the first hypothesis, whereas they review studies of sex differences in developmental processes to test the second. They find moderate support for both hypotheses and present a comprehensive theory of girls' developmental psychopathology that integrates social and developmental influences.

The present study applied a semiparametric mixture model to a sample of 284 low-income boys to model developmental trajectories of overt conduct problems from ages 2 to 8. As in research on older children, 4 developmental trajectories were identified: a persistent problem trajectory, a high-level desister trajectory, a moderate-level desister trajectory, and a persistent low trajectory. Follow-up analyses indicated that initially high and low groups were differentiated in early childhood by high child fearlessness and elevated maternal depressive symptomatology. Persistent problem and high desister trajectories were differentiated by high child fearlessness and maternal rejecting parenting. The implications of the results for early intervention research are discussed, with an emphasis on the identification of at-risk parent-child dyads.

The current study was initiated to increase understanding of developmental cascades in childhood in a sample of at-risk boys (N = 291; 52% White). Mothers, teachers, and boys reported on boys’ externalizing problems, internalizing difficulties, and academic competence. Consistent with hypotheses regarding school-related transitions, high levels of externalizing problems were associated with both low levels of academic competence and high levels of internalizing problems during the early school-age period, and with elevations in internalizing problems during the transition to adolescence. Low levels of academic competence were associated with high levels of internalizing problems in middle childhood, and with high levels of externalizing problems during the transition from elementary school to middle school. Shared risk factors played a minimal role in these developmental cascades. Results suggest that there are cascading effects of externalizing problems and academic competence in childhood and early adolescence, and that some cascading effects are more likely to occur during periods of school-related transitions. Implications of developmental cascade effects for research and intervention are discussed.