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…

Meta-analyses have become the gold standard for synthesizing evidence from multiple clinical trials, and they are especially useful when outcomes are rare or adverse since individual trials often lack sufficient power to detect a treatment effect. However, when zero events are observed in one or both treatment arms in a trial, commonly used…

The paper has three major objectives. The first objective of the paper is to synthesize and define common categories of meta-analysis. The second objective is to propose a way to comprehend these common categories of meta-analysis through learning from their respective generic conceptual frameworks. The third objective is to point out which R…

Learning mathematics in an online learning environment has unique challenges. Success in an online mathematics learning environment depends on a student's self-regulating ability. This systematic review provides the scholarly community with a synthesis of current self-regulated learning (SRL) strategies of students in the mathematics online…

Meta-analyses of educational research findings frequently involve statistically dependent effect size estimates. Meta-analysts have often addressed dependence issues using ad hoc approaches that involve modifying the data to conform to the assumptions of models for independent effect size estimates, such as by aggregating estimates to obtain one…

Meta-analyses play an instrumental role in informing second language (L2) theory and practice. However, current (i.e., classic) approaches to meta-analysis are limited in their ability to do so because they often fail to capture the complexity inherent in primary studies' research designs. As we argue in this article, when complex L2 studies are…

The "LFK" index has been promoted as an improved method to detect bias in meta-analysis. Putatively, its performance does not depend on the number of studies in the meta-analysis. We conducted a simulation study, comparing the "LFK" index test to three standard tests for funnel plot asymmetry in settings with smaller or larger…

Despite the growing interest in incorporating textual glosses into second language (L2) reading in hypermedia and paper media, no agreements have been reached as to whether and what extent a textual gloss facilitates L2 learners' vocabulary acquisition in hypermedia and paper media. The present study meta-analysed the overall effects of textual…

Diverse efforts are underway to reform the journal peer review system. Combined with growing interest in Open Science practices, Open Peer Review (OPR) has become of central concern to the scholarly community. However, what OPR is understood to encompass and how effective some of its elements are in meeting the expectations of diverse communities,…

As a measure of heterogeneity in meta-analysis, the coefficient of variation (CV) has been recently considered, providing researchers with a complement to the very popular I[superscript 2] measure. While I[superscript 2] measures the proportion of total variance that is due to variance of the random effects, the CV is the ratio of the standard…

The variance-stabilizing Freeman-Tukey double arcsine transform was originally proposed for inference on single proportions. Subsequently, its use has been suggested in the context of meta-analysis of proportions. While some erratic behavior has been observed previously, here we point out and illustrate general issues of monotonicity and…

The meta-analytic-predictive (MAP) approach is a Bayesian meta-analytic method to synthesize and incorporate information from historical controls in the analysis of a new trial. Classically, only a single parameter, typically the intercept or rate, is assumed to vary across studies, which may not be realistic in more complex models. Analysis of…

Plenty of research has been carried out in order to determine the effect of gamification on learner motivation. The purpose of this study was to combine the experimental research results examining the effect of gamification on learner motivation and conducted between the years of 2010-2017 through a meta-analysis. The random effects model was used…

Diffraction has emerged as a concept and methodology through opposing reflexivity. In this paper, I argue that reflexivity and diffraction are not external to each other. In contrast, I propose that they blur into each other and so we do not find ourselves using pure reflexivity or diffraction. Furthermore, I contend that categorically…

Publication bias is a ubiquitous threat to the validity of meta-analysis and the accumulation of scientific evidence. In order to estimate and counteract the impact of publication bias, multiple methods have been developed; however, recent simulation studies have shown the methods' performance to depend on the true data generating process, and no…