Module 6 covers the third step when conducting What Works Clearinghouse (WWC) reviews of group design studies: assessing compositional change in the intervention and comparison groups after participants have been assigned to conditions. This module explains why the WWC is concerned with compositional change in randomized controlled trials (RCTs) and how attrition can affect the research ratings of findings from these designs. Chapter 3 describes how the WWC assesses compositional change in cluster-level RCTs.
The WWC offers this training to inform the public about the key elements of the WWC Group Design Standards, increase transparency of our review process, and promote the use of high quality, rigorous research. This training series includes 12 modules (divided into chapters), each focused on a different aspect of the WWC Group Design Standards. It also describes the procedures the WWC uses to review studies and how it reports findings. We recommend viewing the modules in numerical order. Start with the Introduction video, which describes the goals, topics, and organization of this training. The full set of modules are accessible at [ Ссылка ].
The WWC is an investment of the Institute of Education Sciences (IES) within the U.S. Department of Education and was established in 2002. The work of the WWC is managed by a team of staff at IES and conducted under a set of contracts held by several leading firms with expertise in education, research methodology, and the dissemination of education research. For more than a decade, the WWC has been a central and trusted source of scientific evidence on education programs, products, practices, and policies. We review the research, determine which studies meet rigorous standards, and summarize the findings. We focus on high-quality research to answer the question, “What works in education?”
