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What's the Evidence for Evidence-Based Practice?

This article explains why one must be cautious with implementing an evidence-based program. You must "understand the basics of evaluation research, including the statistical methods used to generate evidence of program effectiveness. A study that reports statistically significant results is not necessarily evidence of effectiveness, and being evidence-based does not mean a program is guaranteed to work ... understanding these basic principles of evaluation research is part of every practitioner’s job" (p. 1). This publication clarifies: how evaluation research is limited; statistics are not always significant; effect size is a better assessment metric than statistical significance-effect size combines substantive importance and statistical significance; and while evaluation research should play a role, it cannot utterly have the last word; and some programs will be effective but not evidence-based because there is not enough money to invest in determining the efficacy of every justice program.