In any meta-analysis, it is critically important to report the dispersion in effects as well as the mean effect. If an intervention has a moderate clinical impact "on average" we also need to know if the impact is moderate for all relevant populations, or if it varies from trivial in some to major in others. Or indeed, if the…

Network meta-analysis (NMA) is an established method for assessing the comparative efficacy and safety of competing interventions. It is often the case that we deal with interventions that consist of multiple, possibly interacting, components. Examples of interventions' components include characteristics of the intervention, mode (face-to-face,…

Toward the goal of more rapid knowledge accumulation via better meta-analyses, this article explores statistical approaches intended to increase the precision and comparability of effect sizes from education research. The featured estimate of the proposed approach is a standardized mean difference effect size whose numerator is a mean difference…

This meta-analytic review demonstrates that language interventions can improve oral language in children with neurodevelopmental disorders. We assessed interventions that target language skills in children with neurodevelopmental disorders. The interventions had to use techniques ranging from explicit and structured activities (explicit…

To address the evidence gap in making effective language of instruction (LOI) decisions, we propose a systematic review of the role of LOI choices in education programs and policies on literacy outcomes in multilingual educational contexts in low- and middle-income countries (LMICs). Grounded in a multidisciplinary theory of change (ToC)…

This Campbell systematic review examines the effects of targeted school-based interventions on standardised tests in reading and maths. The review analyses evidence from 71 studies, 52 of which are randomised controlled trials. School-based interventions targeting students with, or at risk of, academic difficulties in Grades 7-12 have on average…

Clinicians, teachers, and researchers have long suspected that there may be some kind of association between poor reading and emotional health. However, for many years, studies of this association were generally sporadic and poor in quality. This article outlines how -- over the last 5 years or so -- national and international associates of the…

When we speak about heterogeneity in a meta-analysis, our intent is usually to understand the substantive implications of the heterogeneity. If an intervention yields a mean effect size of 50 points, we want to know if the effect size in different populations varies from 40 to 60, or from 10 to 90, because this speaks to the potential utility of…

This document summarises key findings from the quantitative strands of a review of the Education Endowment Foundation (EEF) evaluations that had reported from the establishment of EEF in 2011 up to January 2019. The quantitative strands summarised include meta-analyses of effect sizes reported for attainment outcomes and descriptive analyses of…

Much of the evidential basis for recent policy decisions is grounded in effect size: the standardised mean difference in outcome scores between a study's intervention and comparison groups. This is interpreted as measuring educational influence, importance or effectiveness of the intervention. This article shows this is a category error at two…

Bullying is a pervasive problem that impacts children and youth in schools involved as perpetrators, victims, and bystanders. This paper synthesizes findings from the empirical literature, including meta-analyses, to examine the evidence for bullying prevention and intervention approaches with attention to developmental levels (preschool,…

The main goal of the present research is to systematically examine the available evidence for the effectiveness of different types of school-based interventions for reducing disciplinary school exclusion. Secondary goals relate to comparing different approaches (e.g., school-wide management, classroom management, restorative justice,…

A recent meta-analysis of the effect of financial literacy and financial education on downstream financial behaviors has shown a weak collective impact of the work of financial education. While the findings are not stellar, they do not support a dismantling of financial education programs and funding. This paper examines the findings of the…

Social skills training (SST) is increasingly used as an adjunct to academic interventions for children and youth with learning disabilities (LD). A brief context and an overview of SST are provided and the issue related to the establishment of SST efficacy via extant meta-analyses is described. Generally, outcomes for SST efficacy are mixed, at…

Twenty-nine peer-reviewed journal articles that analyzed intervention implementation in schools using single-case experimental designs were meta-analyzed. These studies reported 171 separate data paths and provided 3,991 data points. The meta-analysis was accomplished by fitting data extracted from graphs in mixed linear growth models. This…