We begin with meta-analyses focused nominally on mental health promotion and mental illness/problem behavior prevention programs because these have the most rigorous evaluations. There are several reasons for this: first, there is a long tradition of both mental health promotion and mental illness/problem behavior prevention work; consequently, these programs have had time to develop and to have comprehensive rigorous evaluations completed. Second, many of these programs are being conducted in school buildings during the official school day. These two characteristics make it much easier to conduct a successful randomized trial design evaluation because the participants are drawn from a “captive” population. Conducting such evaluations in community programs is much more difficult precisely because participation is voluntary. We say more about this later in this chapter and in Chapter 7. We then move onto the meta-analyses and summative reviews of largely out-of-school time community programs.
Durlak and Wells (1997, 1998) conducted two meta-analytical reviews of primary and secondary prevention mental health programs operating prior to 1992 for youth under the age of 19. (Primary prevention programs intervene with normal populations to prevent problems from developing. Secondary prevention programs target individuals already at risk or exhibiting problems). Both meta-analyses included only programs with a control group of some type (e.g., a group that is not participating in the program or a group that is on a waiting list to participate in the program). Randomized designs were used in 61 percent of the primary prevention program evaluations and 71 percent of the secondary prevention program evaluations. The primary prevention review (Durlak and Wells, 1997) included 177 programs; the secondary prevention review (Durlak and Wells, 1998) included 130 evaluations. Finally, most of these programs took place in schools (a likely reason that these studies had such low attrition rates of young people leaving the program before completion and final testing).
In general, the results suggest that preventive mental health programs can be effective across a variety of psychological outcome measures for periods of up to two years following the intervention exposure. They are particularly effective at increasing such personal competencies as