Randomized clinical trials underpin evidence-based clinical practice, but flaws in their conduct may lead to biased estimates of intervention effects and hence invalid treatment recommendations. The main approach to the empirical study of bias is to collate a number of meta-analyses and, within each, compare the results of trials with and without…

Background: Stratified medicine seeks to identify patients most likely to respond to treatment. Individual participant data (IPD) network meta-analysis (NMA) models have greater power than individual trials to identify treatment-covariate interactions (TCIs). Treatment-covariate interactions contain "within" and "across" trial…

This "What Works Clearinghouse Procedures and Standards Handbook (Version 3.0)" provides a detailed description of the standards and procedures of the What Works Clearinghouse (WWC). The remaining chapters of this Handbook are organized to take the reader through the basic steps that the WWC uses to develop a review protocol, identify…

The success of an intervention depends not only upon its theoretical soundness, but also on proper implementation that reflects the guidelines derived from its theoretical conception. Debates surrounding the effectiveness of problem-based learning (PBL) have focused on its theoretical conception and students' learning outcomes, but implementation…

Education reform is increasingly portrayed as a quest to achieve a "world class" education system through a process of identifying and adopting the practices of those systems whose pupils perform best in league tables of achievement. This is the rationale for the range of new policies proposed by the coalition government in the schools…

Schools and school systems throughout the nation are increasingly experimenting with using various instructional technologies to improve productivity and decrease costs, but evidence on both the effectiveness and the costs of education technology is limited. A recent report published by the Thomas B. Fordham Institute sets out to describe "the…

Recent findings from a Mathematica study comparing the performance of teachers prepared via alternative and traditional routes have been interpreted to suggest that policymakers and practitioners should expand the use of fast-entry alternative routes and seek teachers trained through such programs, as they presumably perform as well in the…

The Center for Research on Education Outcomes (CREDO) at Stanford University conducted a large-scale analysis of the impact of charter schools on student performance. The center's data covered 65-70% of the nation's charter schools. Although results varied by state, 17% of the charter school students have significantly higher math results than …

This report collects the results of all available studies using valid empirical methods to compare segregation in public and private schools, both in general and in the context of school voucher programs. Examining the widespread claims that private schools have high segregation levels and vouchers will lead to greater segregation, this report…