Evidence-based education aims to support policy makers choosing between potential interventions. This rarely involves considering each in isolation; instead, sets of evidence regarding many potential policy interventions are considered. Filtering a set on any quantity measured with error risks the "winner's curse": conditional on…

This paper seeks to raise awareness among educational researchers and practitioners of some significant weaknesses and internal contradictions of randomised control trials (RCTs). Although critiques throughout the years from education scholars have pointed to the detrimental effects of this experimental approach on education practice and values,…

Evidence-based policy at the local level requires predicting the impact of an intervention to inform whether it should be adopted. Increasingly, local policymakers have access to published research evaluating the effectiveness of policy interventions from national research clearinghouses that review and disseminate evidence from program…

Across the evidence-based policy and practice (EBPP) community, including education, randomised controlled trials (RCTS) rank as the most "rigorous" evidence for causal conclusions. This paper argues that that is misleading. Only narrow conclusions about study populations can be warranted with the kind of "rigour" that RCTs…

The paradigm of evidence-based education continues to inform the development of policy in a number of countries. At its simplest level, evidence-based education incorporates evidence, often that provided by randomised controlled trials, into classroom practice. England's Education Endowment Foundation is in the process of exporting evidence-based…

Within evidence-based education, results from randomised controlled trials (RCTs), and meta-analyses of them, are taken as reliable evidence for effectiveness -- they speak to "what works". Extending RCT results requires establishing that study samples and settings are representative of the intended target. Although widely recognised as…

This article addresses the gap between what works in research and what works in practice. Currently, research in evidence-based education policy and practice focuses on randomized controlled trials. These can support causal ascriptions ("It worked") but provide little basis for local effectiveness predictions ("It will work…

School-based evaluations of interventions are increasingly common in education research. Ideally, the results of these evaluations are used to make evidence-based policy decisions for students. However, it is difficult to make generalizations from these evaluations because the types of schools included in the studies are typically not selected…

The place of evidence to inform educational effectiveness has received increasing attention internationally in the last two decades. An important contribution to evidence-informed policy has been greater attention to experimental trials including randomised controlled trials (RCTs). The aim of this paper is to examine the use of evidence,…

As a systemic approach to improving educational practice through research, "What Works" has come under repeated challenge from alternative approaches, most recently that of improvement science. While "What Works" remains a dominant paradigm for centralized knowledge-building efforts, there is need to understand why this…

National governments use evidence selectively to argue that a successful policy intervention in one local area should be emulated in others ("evidence-based best practice"). However, the value of such evidence is always limited because there is: disagreement on the best way to gather evidence of policy success, uncertainty regarding the…

Given increasing interest in evidence-based policy, there is growing attention to how well the results from rigorous program evaluations may inform policy decisions. However, little attention has been paid to documenting the characteristics of schools or districts that participate in rigorous educational evaluations, and how they compare to…

This report describes in detail how researchers, policymakers, and program administrators can recognize opportunities for experiments and carry them out. Specifically, the report focuses on opportunistic experiments, defined as randomized controlled trials (RCTs) that study the effects of initiatives, program changes, or policy actions that…

As evidence-based reform becomes increasingly important in educational policy, it is becoming essential to understand how research design might contribute to reported effect sizes in experiments evaluating educational programs. The purpose of this study was to examine how methodological features such as types of publication, sample sizes, and…

Research methods are tools that can be variously applied - depending on the stage of knowledge in a particular area, the type of research question being asked, and the context of the research. The field of program evaluation, critical for social policy development, often has not adequately embraced the full range of methodological tools needed to…