Since the 1990s, there have been repeated calls for the systematic use of randomised controlled trials (RCTs) to inform educational decision-making. The advent of the Education Endowment Foundation (EEF) -- described as England's What Works Centre for Education -- in 2011 has made this a reality in England: by 2020, over a third of English schools…

The field of educational research encompasses a vast array of paradigmatic and methodological perspectives. Arguably, this range has both expanded and limited our achievements in the name of educational research. In Australia, the ascendancy of certain research perspectives has profoundly shaped the field and its likely future. We (are expected…

Recent studies show cluster randomized trials may be well powered to detect mediation or indirect effects in multilevel settings. However, literature has rarely provided guidance on designing cluster-randomized trials aim to assess indirect effects. In this study, we developed closed-form expression to estimate the variance of and the statistical…

Randomized controlled trials (RCTs) admit unconfounded design-based inference--randomization largely justifies the assumptions underlying statistical effect estimates--but often have limited sample sizes. However, researchers may have access to big observational data on covariates and outcomes from RCT non-participants. For example, data from A/B…

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…

Interventions often require multiple decisions to improve outcomes for every student. Whether the decision to implement a practice, tailor an existing protocol, or change approaches, these decisions should be based on individual variables and outcomes via a sequence of treatment. To develop adaptive interventions that have sufficient evidence to…

Experimental studies are often employed to test the effectiveness of teaching innovations such as new pedagogy, curriculum, or learning resources. This article offers guidance on good practice in developing research designs, and in drawing conclusions from published reports. Random control trials potentially support the use of statistical…

The primary aim of this study was to assess the efficacy of a childcare-based intervention in increasing child physical activity by allowing children unrestricted access to outdoor areas for free-play when structured activity is not taking place. A randomized controlled trial was conducted in six childcare services. Intervention services provided…

This study examined the treatment efficacy of "PEERS"® (Program for the Education and Enrichment of Relational Skills) among Chinese adolescents with autism spectrum disorder (ASD) in Hong Kong. The original "PEERS"® manual was translated into Chinese, and cultural adjustments were made according to a survey among 209 local…

Using an RD design provides statistically robust estimates while allowing researchers a different causal estimation tool to be used in educational environments where an RCT may not be feasible. Results from External Evaluation of the i3 Scale-Up of Reading Recovery show that impact estimates were remarkably similar between a randomized control…

Multilevel experiments have been widely used in education and social sciences to evaluate causal effects of interventions. Two key considerations in designing experimental studies are statistical power and the minimal use of resources. Optimal design framework simultaneously addresses both considerations. This dissertation extends previous optimal…

Background: In fall 2020, community colleges (CCs) served nearly five million students, representing 29% of U.S. undergraduates. Despite providing unprecedented access to postsecondary education, rates of degree attainment are low. Among first-time, full-time, degree/certificate-seeking students whose first postsecondary school is a CC, only 31%…

This article assesses the likely generalizability of educational treatment-effect estimates from regression discontinuity designs (RDDs) when treatment assignment is based on academic pretest scores. Our assessment uses data on outcome and pretest measures from six educational experiments, ranging from preschool through high school, to estimate…

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…

This article assesses the likely generalizability of educational treatment-effect estimates from regression discontinuity designs (RDDs) when treatment assignment is based on academic pretest scores. Our assessment uses data on outcome and pretest measures from six educational experiments, ranging from preschool through high school, to estimate…