The biopsychosocial perspective on conduct disorder articulated here has important implications for preventive intervention practice and prevention research. These ideas are consistent with those that form the basis for the Fast Track prevention experiment (Conduct Problems Prevention Research Group, 1992
). The first implication is that high-risk children can be identified with reasonable accuracy in early life, at least by the beginning of elementary school (Lochman & Conduct Problems Prevention Research Group, 1995
). By screening children in violent neighborhoods for emergent conduct problems, the predictive accuracy may be greater than 50%, which is quite a strong relation given much lower overall base rates for serious conduct-problem outcomes. Prediction of single acts of violence is a more precarious enterprise, and accuracy is far lower; however, the field has now matured to the point where 50% accuracy in the prediction of adolescent chronic conduct problems from early childhood factors is within reach. Prevention efforts with a targeted subgroup of high-risk children can also begin fairly early in life, prior to the time that neural paths are irreversibly canalized and antisocial outcomes are inevitable and no longer malleable.
The potential effectiveness of early screening has major consequences for public policy. Schools can play a more active role than they have in the past in identifying children at a young age who might benefit from preventive intervention. If efficacious prevention programs are identified, funding can be moved from after-the-fact programs in late adolescence to early intervention efforts. One major caution about this recommendation is that early identification also opens the possibility of labeling and latrogenic effects of intervention. Practitioners must be cautious to ensure that their efforts do not lead to public labeling of children or long-term deleterious outcomes of the kind documented by Dishion et al. (1999)
The second implication is that prevention during the early stages of the evolution of chronic conduct problems is more likely to be successful than intervention in adolescence, after antisocial outcomes have become inevitably overdetermined. Treatment with aggressive adolescents is highly frustrating for clinicians, but prevention with young children offers hope.
The third implication is that preventive intervention studies can take either of two forms. First, experiments are needed in which a single component of a developmental model is manipulated through intervention in order to observe whether its change has predicted proximal effects. For example, one might try to teach parents to use nonviolent behavior management strategies in order to observe the immediate effect on their children (see, e.g., Patterson et al., 1992
). The model presented here suggests that any single-component intervention is unlikely to lead to long-lasting change in chronic conduct problems because multiple other forces act to support antisocial development. However, a single-component study is a way to test developmental theory and is a building block toward the second kind of intervention, which is a field trial. The goal of a prevention field trial is to test an overall developmental model through experimental manipulation of proximal processes in order to test the effects of those processes on long-term outcomes.
In a large field trial, the sociocultural context could be the object of change through universal interventions. Cultural context factors play roles in conduct problems; the major driving forces for an individual child are life experiences of parenting, peers, and schooling and cognitive and emotional processes. Preventive interventions should be directed toward these domains and should be integrated in a coordinated manner. Because multiple factors conspire to produce conduct-problem outcomes, intervention must be directed toward all, or at least many, of these components. Otherwise, the effects of intervention may be offset by factors that promote antisocial development.
This model suggests that preventive interventions must span from childhood to adolescence, because new risk factors emerge at each new developmental era. Analogies to prevention in health and illness are useful here. The proposed model suggests that one-time immunization (as in a polio vaccine) is unlikely to lead to long-term prophylactic effects. Instead, preventive dentistry provides a more apt analogy, with the need for daily brushing of teeth being a useful reminder that ongoing management of child development may be necessary to prevent chronic conduct problems in adolescence.
Another implication is that preventive interventions at any time point must be sensitive to the cultural context and developmental level of a child. Interventions with White European American families may not be appropriate for African American families (Hammond & Yung, 1994
). A field trial at the school-onset switchpoint should be based on risk factors at that time point and, thus, might include parent training in contingent behavior management, peer pairing to enhance friendships, academic tutoring, social-cognitive skill training, exposure to benign instead of hostile life experiences, and classroom-wide curricula designed to change the child’s sociocultural context. The intervention might continue at other switchpoints across childhood to include components that are responsive to developmentally emergent challenges. In early adolescence, peer pressure, puberty, and a growing sense of self-identity represent new challenges, so intervention at that switchpoint should address those challenges.
Because adolescent conduct problems are correlated with a variety of other behavior problems (Jessor et al., 1991
), field trial evaluations should include a variety of outcome measures. Proximal mediating processes should be assessed in order to observe whether an intervention is operating in the hypothesized manner before the long-term outcome is known. Data analyses should focus on the process-to-outcome relation in order to test the hypothesis that proximal process changes account for intervention effects on long-term outcomes. Also, one might assess a range of correlated outcomes, such as illicit drug use, dropping out of school, career orientation, and sexual behavior.
The array of types of prevention research that is suggested here is broad (Dodge, 2001
). It includes narrow studies of how to intervene with discrete processes and well-controlled programs that are administered under the relatively pristine circumstances of the university, called efficacy studies
. It also includes studies of prevention programs as they are administered in community settings, called effectiveness studies
. Finally, it includes studies in the realm of public policy, such as cost–benefit analyses, analyses of political viability, and studies of community ownership (Dodge, 2001
Finally, this model suggests that there is room for optimism in prevention research. One reason that behavior geneticists are sometimes rejected in the prevention field is that preventionists read their work to imply that birth is destiny. And one reason that sociocultural theorists are sometimes ignored is that they paint a picture that requires global economic and political change in order to keep children from growing up to be violent. This model fully embraces the perspectives of biological as well as sociocultural theorists, but it suggests that the proximal mechanisms of development operate through life experiences and psychological processes. It is these processes that might be changed through prevention.