The committee-reviewed numerous prevention programs that were supported by federal agencies and private foundations. A wide net was cast in soliciting nominations, but the search could not be exhaustive. A majority of the prevention programs that currently exist are service programs and demonstrations that have not incorporated rigorous research methodologies. Even those that have an evaluation component usually have not used rigorous standards for assessment of effectiveness. Thus the nation is spending billions of dollars on programs whose effectiveness is not known. Most of the prevention programs discussed in this chapter meet the criteria listed below, including the use of a randomized controlled trial design. Such a high standard lends credence to the results of these studies. These program illustrations demonstrate that rigorous protocols can be applied to complex interventions, yielding tangible outcomes.
Many of the prevention programs that were reviewed used quasi-experimental designs. Where their findings provide some confirmatory evidence for a study with a randomized controlled trial design, or where their findings provide new leads in areas where there have been no randomized controlled studies, the information is briefly discussed in the chapter. Also, three well-known service projects that have not been rigorously evaluated are presented to highlight the potential for applying experimental designs to preventive interventions created by practitioners. All prevention program titles are in italics. Titles of programs that met the criteria for use as full illustrations are preceded by an asterisk. These illustrative programs are also listed in Table 7.1 and are abstracted in more detail in the background materials (program abstracts are available as indicated in Appendix D).
The programs target different age groups and are arranged here in developmental sequence from gestation through old age. As individuals move from one stage to the next, the developmental tasks facing them change, as does the nature of the risk and protective factors. This life course presentation serves to emphasize the importance of continuity and integration of interventions across the entire life span. Prevention programs that lasted for several years and bridged successive developmental phases or had effects on more than one generation are presented in this chapter at the earliest developmental phase. At the end of each section, several findings and leads that emerged from the review of programs addressing that age group are listed. The order of the points does not imply priority, and the list is not meant to be comprehensive but rather to illustrate the sorts of patterns, problems, and directions for future work that can be learned from such a perspective.