Background: Using meta-analytic review techniques, this study synthesized the results of 79 unpublished studies about the nature of transformational school leadership (TSL) and its impact on the school organization, teachers, and students. This corpus of research associates TSL with 11 specific leadership practices. These practices, as a whole,…

As evidence-based reform becomes increasingly important in educational policy, it is becoming essential to understand how research design might contribute to reported effect sizes in experiments evaluating educational programs. The purpose of this study was to examine how methodological features such as types of publication, sample sizes, and…

Over the past decade postsecondary education has been moving increasingly from the classroom to online. During the fall 2010 term 31 percent of U.S. college students took at least one online course. The primary reasons for the growth of e-learning in the nation's colleges and universities include the desire of those institutions to generate…

Systematic reviews and meta-analysis are techniques for synthesizing primary empirical studies to produce a summary of effects. To facilitate this goal, the Campbell Collaboration (C2) supports reviews within the disciplines of crime and justice, education, international development, and social welfare. At the annual Campbell Colloquium, experts…

This succinct and jargon-free introduction to effect sizes gives students and researchers the tools they need to interpret the practical significance of their results. Using a class-tested approach that includes numerous examples and step-by-step exercises, it introduces and explains three of the most important issues relating to the practical…

One of the main objectives in meta-analysis is to estimate the overall effect size by calculating a confidence interval (CI). The usual procedure consists of assuming a standard normal distribution and a sampling variance defined as the inverse of the sum of the estimated weights of the effect sizes. But this procedure does not take into account…

Meta-analytic reliability generalizations (RGs) are limited by the scarcity of reliability reporting in primary articles, and currently, RG investigators lack a method to quantify the impact of such nonreporting. This article introduces a stepwise procedure to address this challenge. First, the authors introduce a formula that allows researchers…

The purpose of the present study was to meta-analytically investigate the score reliability for the Satisfaction With Life Scale. Four-hundred and sixteen articles using the measure were located through electronic database searches and then separated to identify studies which had calculated reliability estimates from their own data. Sixty-two…

The Adult Literacy Research Working Group (ALRWG), a panel of experts on adult reading research and practice, was established by the National Institute for Literacy (NIFL) in collaboration with the National Center for the Study of Adult Learning and Literacy (NCSALL). It was part of the Institute's efforts to provide educators, parents and others…

Objective: To clarify the nature and extent of differences in the ways that physically abusive, neglectful, and non-maltreating parents communicate during interactions with their children. Method: A meta-analysis was conducted of 33 observational studies comparing parent-child interactions in families where parents have a documented history of…

The mathematical representation of E. Brunswik's (1952) lens model has been used extensively to study human judgment and provides a unique opportunity to conduct a meta-analysis of studies that covers roughly 5 decades. Specifically, the authors analyzed statistics of the "lens model equation" (L. R. Tucker, 1964) associated with 249 different…

In the past two decades, numerous meta-analyses have been published that examine the question of psychotherapy equivalence. Hunsley and Di Giulio (2002) critically reviewed this literature and concluded that there was abundant evidence that the Dodo bird verdict of equivalence across psychotherapies is false. In this article, we summarize and…

Federal standards established in 1997 allow respondents to select multiple-race categories. These new standards changed the single-race subgroup definitions that the government has required since 1977. Meta-analysis, research on long-term assessment trends, and other research involving historical comparisons must account for the definitional…

Bridging the gap between lab and clinic has become a rallying cry for a generation of treatment researchers, and identifying and overcoming barriers to successful dissemination of best-practice treatment has become a major public mental health priority. In this review, the authors argue that a key limit to accomplishing this goal may be found back…

A search of the ERIC database, Academic Search Premier, and a review of literature suggests that meta-analysis is ignored by career and technical education (CTE) researchers, a situation that is regrettable but remediable. The purpose of this paper was to provide CTE researchers and consumers with selected procedures and guidelines for conducting…