Using a sample of 70,399 published p-values from 192 meta-analyses, we empirically estimate the counterfactual distribution of p-values in the absence of any biases. Comparing observed p-values with counterfactually expected p-values allows us to estimate how many p-values are published as being statistically significant when they should have been…

Meta-analysts often encounter missing covariate values when estimating meta-regression models. In practice, ad hoc approaches involving data deletion have been widely used. The current study investigates the performance of different methods for handling missing covariates in meta-regression, including complete-case analysis (CCA), shifting-case…

We aimed to explore, in a sample of systematic reviews (SRs) with meta-analyses of the association between food/diet and health-related outcomes, whether systematic reviewers selectively included study effect estimates in meta-analyses when multiple effect estimates were available. We randomly selected SRs of food/diet and health-related outcomes…

Objectives: This systematic review aimed to quantify differences in loneliness levels between autistic and neurotypical samples and investigate the association between loneliness and mental health in autistic individuals. Methods: Three meta-analyses were conducted. Studies were methodologically appraised using established tools. Results: Overall,…

Multiple baseline (MB) designs are becoming more prevalent in educational and behavioral research, and as they do, there is growing interest in combining effect size estimates across studies. To further refine the meta-analytic methods of estimating the effect, this study developed and compared eight alternative methods of estimating intervention…

In this study, a meta-analysis of reading and listening comprehension comparisons across age groups was conducted. Based on robust variance estimation (46 studies; N = 4,687), the overall difference between reading and listening comprehension was not reliably different (g = 0.07, p = 0.23). Reading was beneficial over listening when the reading…

This systematic review and meta-analysis examined interventions targeting play skills of children with autism spectrum disorder (ASD) involving typically developing (TD) peers. The objectives of this work are to (a) identify and describe the characteristics and components of interventions aimed at improving play skills in children with ASD and…

Systematic reviews with meta-analyses are powerful tools that can answer research questions based on data from published studies. Ideally, all relevant data is directly available in the text or tables, but often it is only presented in graphs. In those cases, the data can be extracted from graphs, but this potentially introduces errors. Here, we…

Methods for indirect comparisons and network meta-analysis use aggregate level data from multiple studies. A very common, and closely related, scenario is where a company has individual patient data (IPD) from its own trial, but only has published aggregate data from a competitor's trial, and an indirect comparison of the treatments evaluated in…

The purpose of this meta-analysis was to examine prior research that compared the differences between the academic performance of students who undertook online homework as against those that undertook traditional pen and pencil homework. Eighteen experimental and quasi-experimental studies met inclusion criteria for the meta-analysis. Eleven found…

Misinformation around scientific issues is rampant on social media platforms, raising concerns among educators and science communicators. A variety of approaches have been explored to confront this growing threat to science literacy. For example, refutations have been used both proactively as warning labels and in attempts to inoculate against…

Purpose: Early language and communication interventions for children with language impairments have been shown to be effective in assessments administered immediately after treatment. The purpose of the current systematic review and meta-analysis was to assess the overall durability of those effects over time and whether durability was related to…

Consistently in achievement goal research, pursuing performance-avoidance goals has been associated with a decrease in achievement. Less is known to what extent this effect depends on the reasons underlying these goals' endorsement. The present research uses a social value approach to assess how do performance-avoidance goals' effects on…

The present meta-analysis investigated the effects of recasts along with a number of moderating variables on L2 development by meta-analysing the results of 24 primary studies. The findings revealed an overall medium effect size for the effectiveness of recasts (g = 0.70, 95% CI = 0.48-0.93). Furthermore, the findings indicated that recasts are…

This meta-analysis includes experimental and quasi-experimental studies of reading interventions for English learners (ELs) coupled with four specific instructional strategies. The purposes of this meta-analysis were two-fold: (1) to identify the effects of the four instructional strategies (i.e. scaffolding, graphic organizers, interactive read…