In summary, the present study considered the development of externalizing problems as a function of early risk factors along with successive risk and protective factors from early childhood to adulthood. The development of externalizing problems can be described in terms of multiple domains of risk—both from their momentum of adjustment (i.e., continuity) and from other risk across multiple developmental eras. The specific risk factors explained variance in the development of externalizing problems above and beyond the strong continuity of externalizing problems. Moreover, the continuity of externalizing problems was nonlinear across time. The findings support a model that simultaneously takes into account numerous characteristics of children and their living situations, and predicts trajectories of externalizing problems with a moderately high degree of accuracy. The study also suggests that the modeled trajectories and their predictions are also meaningful for important societal outcomes including arrests, illegal drug use, and drunk driving. Nevertheless, there remains much room for improvement in terms of predictive precision. We expect to see improvements from: 1) further specification of the causal mechanisms, 2) the consideration of additional risk factors from other domains (e.g., genetics), and 3) modeling interactions among risk factors.
