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…

As traditionally conceived, publication bias arises from selection operating on a collection of individually unbiased estimates. A canonical form of such selection across studies (SAS) is the preferential publication of affirmative studies (i.e., those with significant, positive estimates) versus nonaffirmative studies (i.e., those with…

In the 2018 meta-analysis of "Educational Psychology Review" entitled "Null effects of perceptual disfluency on learning outcomes in a text-based educational context" by Xie, Zhou, and Liu, we identify some errors and inconsistencies in both the methodological approach and the reported results regarding coding and effect sizes.…

This response aims to critically evaluate the methodology and aims of the meta-analytic review written by Maggin and Johnson (2014). The present authors systematically provide responses for each of the original criticisms and highlight concerns regarding Maggin and Johnson's methodology, while objectively describing the current state of evidence…

Background: Stratified medicine seeks to identify patients most likely to respond to treatment. Individual participant data (IPD) network meta-analysis (NMA) models have greater power than individual trials to identify treatment-covariate interactions (TCIs). Treatment-covariate interactions contain "within" and "across" trial…

Meta-analyses in orphan diseases and small populations generally face particular problems, including small numbers of studies, small study sizes and heterogeneity of results. However, the heterogeneity is difficult to estimate if only very few studies are included. Motivated by a systematic review in immunosuppression following liver…

Outdoor adventure education (OAE) has a long history of being credited with the personal and social development (PSD) of its participants. PSD is notoriously difficult to measure quantitatively, yet stakeholders demand statistical evidence that given approaches to eliciting PSD are effective in their methods. Rightly or wrongly, many stakeholders…

This paper examines sources of potential bias in systematic reviews and meta-analyses which can distort their findings, leading to problems with interpretation and application by practitioners and policymakers. It follows from an article that was published in the "Canadian Journal of Communication" in 1990, "Integrating Research…

Overlap-based measures are increasingly applied in the synthesis of single-subject research. This article considers two criticisms of overlap-based metrics, specifically that they do not measure magnitude of effect and do not adequately correspond with visual analysis. It is argued that these criticisms are based on fundamental misconceptions…

Background: The efficacy of three dietary treatments for ADHD has been repeatedly tested in randomized controlled trials (RCTs). These interventions are restricted elimination diets (RED), artificial food colour elimination (AFCE) and supplementation with free fatty acids (SFFA). There have been three systematic reviews and associated…

This is the first of a two-part article that aims to chart the contemporary landscape of research on teacher preparation and certification. It is based on a review of more than 1,500 studies published between 2000 and 2012. Part 1 provides information about how the review was conducted and describes the theoretical/analytic framework the authors…

This paper explores the methodological approaches most commonly adopted in the scholarly literature on Massive Open Online Courses (MOOCs), published during the period January 2008-May 2014. In order to identify trends, gaps and criticalities related to the methodological approaches of this emerging field of research, we analysed 60 papers…

Research and scholarship into educational effectiveness research (EER) is comprehensively reviewed from the UK, The Netherlands, the US, Cyprus, Belgium, Sweden, France, Germany, New Zealand, Australia, and other societies, dating from the field's origins in the 1970s. Issues include its history, methodological and theoretical advances, scientific…

The article continues the discussion of the five quality principles proposed by Heikkinen, Huttunen, and Syrjala, published in 2007 in "Educational Action Research". In the present article, the authors reconsider the five principles: historical continuity; reflexivity; dialectics; workability; and evocativeness. These five principles are…

Today, nearly forty years after writing centers first began to proliferate, it is worthwhile to reflect on the themes that emerge from empirical material surrounding writing center assessments, for reflecting on these themes may help administrators to refine current assessment practices and scholars to redirect their research. The goal of this…