Historical review of school-based randomized trials for evaluating problem behavior prevention programs

The authors provide a historical review of developments in the methods of school-based evaluations of problem behavior prevention interventions. The design and statistical methodologies used in school-based intervention research have advanced tremendously over the past twenty years. Methods have improved for approaches to the randomization of whole schools, the choice of appropriate comparison or control groups, solutions when randomization breaks down, limiting and handling of variation in integrity of the intervention received, limiting biases introduced by data collection, awareness of the effects of intensive and long-term data collection, limiting and analysis of subject attrition and other missing data, approaches to obtaining parental consent for children to engage in research, design and analysis issues when only small numbers of schools are available or can be afforded, the choice of the unit of analysis, phases of research, optimizing and extending the reach of interventions, and differential effects in subpopulations. The authors conclude that sequential planning, timing, keeping up with methodological advances, publication of results, and accumulation of knowledge are all important in conducting high-quality school-based intervention research, and that the devil is in the details.