Catalano et al. (1999) concluded that two general program strategies were evident in the most effective programs: skill building and environmental/organizational change. A focus on social or cognitive behavioral skills occurred in 96 percent of the programs; decision-making and self-management skills in 73 percent; coping skills in 62 percent; and refusal-resistance skills in 50 percent. Effective environmental or organizational change programs focused on influencing teacher classroom practices and peer social norms.
This review of youth programs was very comprehensive. Catalano et al. concluded that positive youth development approaches could, when implemented well, increase positive youth behavior outcomes and decrease youth problem behaviors. In 19 of the programs reviewed, positive changes in youth behavior included significant improvements in interpersonal skills, quality of peer and adult relationships, self-control, problem solving, cognition, self-efficacy, commitment to schooling, and academic achievement. Of the programs reviewed, 24 showed significant reduction in problem behaviors, including drug and alcohol use, school misbehavior, aggressive behavior, violence, truancy, high-risk sexual behavior, and smoking.
However, Catalano et al. also noted that many of the evaluations themselves had limitations. Of the 25 programs meeting the inclusion criteria, only 64 percent used experimental designs with randomization and only half gathered any follow-up data. None included comprehensive information about the program, the implementation process, the youth development constructs being addressed, or the relation between the implementation information and outcomes. Also, assessment measures were rarely adequate to track positive youth development over time, and problem behaviors were measured much more frequently than positive behaviors. Consequently, much more research is needed before one can be confident about which programs and which aspects of these programs actually impact youth development. Nonetheless, the findings are promising enough that they can be used to inform future program design and to make decisions about which programs are ready for more rigorous evaluation.
Roth et al. (1998a) reviewed over 60 evaluations of prevention and intervention programs for adolescents that incorporated positive youth