Introduction: Missing data are bound to occur in education intervention research. Reasons vary but always have the consequence of reducing sample sizes and can, under certain conditions, seriously bias estimated intervention effects. A wide array of methods have been developed for handling missing data (Enders, 2023). Whereas older approaches…

Randomized experiments are a strong design for establishing impact evidence because the random assignment mechanism theoretically allows confidence in attributing group differences to the intervention. Growth of randomized experiments within educational studies has been widely documented. However, randomized experiments within education have…

Introduction: The What Works Clearinghouse (WWC) reviews rigorous research on educational interventions with a goal of identifying "what works" and making that information accessible to educators and policymakers. In rating the quality of causal research, the WWC has historically prioritized internal validity over external validity. One…

Introduction: Concerns about the risk of bias (RoB) of Meta-analysis (MAs) have grown in parallel with the exponential increase in the number of publications in science. However, this has not been properly assessed in Education. The aims were to evaluate the RoB of MAs in Education and to identify potential predictors of a lower RoB. Methods:…

Randomized controlled trials have proliferated in education, in part because they provide an unbiased estimator for the causal impact of interventions. It is increasingly recognized that many such trials in education have low power to detect an effect if indeed there is one. However, it is less well known that low powered trials tend to…

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…

In this commentary on John Raven's "Diving in Where Angels Fear to Tread: Pre-Requisites to Evidence-Based Interventions," Tommy MacKay discusses three examples that illustrate Raven's tendency to overstate or at least to over-simplify the issues raised in his paper and to present various views, approaches, or interventions as being…

John Raven has the capacity to see a bigger picture and highlight some of the causes of failures of that bigger picture. In barely 6000 words, he manages to outline several meta and micro-level problems that have led to the position he outlines regarding evidence-based interventions. This achievement should not be overlooked; what he has managed…

In this article John Raven responds to commentaries on his article, "Diving in Where Angels Fear to Tread: Pre-Requisites to Evidence-Based Interventions" (EJ1248321). Herein, he provides dialogues with individual authors that relate closely to his original theme and which seemed to merit further elaboration. He briefly addresses: (1)…

Panel data methods, which include difference-in-differences and comparative interrupted time series, have become increasingly common in education policy research. The key idea is to use variation across time and space (e.g., school districts) to estimate the effects of policy or programmatic changes that happen in some localities but not others.…

Panel data methods, which include difference-in-differences and comparative interrupted time series, have become increasingly com- mon in education policy research. The key idea is to use variation across time and space (e.g., school districts) to estimate the effects of policy or programmatic changes that happen in some localities but not others.…

This protocol guided the review of research that informs the What Works Clearinghouse (WWC) practice guide entitled "Strategies for Postsecondary Students in Developmental Education -- A Practice Guide for College and University Administrators, Advisors, and Faculty." This protocol was used in conjunction with the "WWC Procedures…

Comparison studies conducted to determine which instructional interventions are most efficient for teaching discrete behaviors to individuals with disabilities are potentially valuable, although some threats to internal validity may be more likely in these studies. Studies included in this review typically met common internal validity standards,…

A substantial number of randomized trials of educational interventions that have been conducted over the past two decades have produced null results, with either no impact or an unreliable estimate of impact on student achievement or other outcomes of interest. The investment of time and money spent implementing such trials warrants more useful…

Over the past 15 years, we have seen an increase in the use of cluster randomized trials (CRTs) to test the efficacy of educational interventions. These studies are often designed with the goal of determining whether a program works, or answering the what works question. Recently, the goals of these studies expanded to include for whom and under…