RESUMEN
Comprehensive community initiatives (CCIs) represent a popular method for creating systemic change, yet there is a dearth of evidence on their effectiveness (Zaff, Pufall Jones, Donlan, Lin, & Anderson, 2016). This article presents a systematic review of the evidence on the population-level impact of CCIs, focusing specifically on documented effects from studies using an experimental or quasi-experimental design. Of 1,947 articles identified through a database and hand search, 25 articles examining six different CCIs-most of which employed prevention science frameworks-met the review inclusion criteria. The results of this review show that CCIs can strengthen protective factors and reduce risk factors, delay initiation of and reduce substance use, and reduce the likelihood of, and delay engagement in, violent and/or delinquent behaviors. Impacts have been documented as soon as one year after initial intervention, and as early as 7th grade, with effects sustained as long as seven years post-intervention, and as late as a year post-high school. However, relative to the prevalence of CCIs as a practical intervention, the evidence base is small, potentially dated, and focused on a narrow set of outcomes and populations. Recommendations for interpreting the evidence base are discussed, including methodological limitations and implications for future work.