Purpose: This article provides benchmark data on within-group effect sizes from published randomized clinical trials supporting the efficacy of dialectical behavioral therapy (DBT) for borderline personality disorder (BPD) in adults aged 18-65 years. Method: Within-group effect sizes were calculated via the Glass approach and adjusted for sample…

The What Works Clearinghouse (WWC) is an initiative of the U.S. Department of Education's Institute of Education Sciences (IES), which was established under the Education Sciences Reform Act of 2002. It is an important part of IES's strategy to use rigorous and relevant research, evaluation, and statistics to improve the nation's education system.…

This article examines the statistical precision of cluster randomized trials (CRTs) funded by the Institute of Education Sciences (IES). Specifically, it compares the total number of clusters randomized and the minimum detectable effect size (MDES) of two sets of studies, those funded in the early years of IES (2002-2004) and those funded in the…

The What Works Clearinghouse (WWC) systematic review process is the basis of many of its products, enabling the WWC to use consistent, objective, and transparent standards and procedures in its reviews, while also ensuring comprehensive coverage of the relevant literature. The WWC systematic review process consists of five steps: (1) Developing…