Purpose: This study presents a meta-analysis of the difference in nonword repetition performance between children with and without specific language impairment (SLI). The authors investigated variability in the effect sizes (i.e., the magnitude of the difference between children with and without SLI) across studies and its relation to several…

The objective of this report is to review studies that report language and literacy outcomes associated with preschool curriculum-based interventions. Results from studies reporting on interventions targeting preschool children from low-income families were included regardless of the specific type of program. Although the majority of preschool…

This report describes the findings of an analysis of a series of action research projects conducted by Goshen Community Schools at the elementary school level. During the 2008-2009 school year, 26 teachers at 7 elementary schools participated in independent action research studies regarding the extent to which a six step approach to direct…

This report describes the findings of an analysis of a series of action research projects conducted by Goshen Community Schools at the middle school level. During the 2008-2009 school year, six teachers at Goshen Middle School participated in independent action research studies regarding the extent to which a six step approach to direct vocabulary…

This report describes the findings of an analysis of a series of action research projects conducted by Goshen Community Schools at the high school level. During the 2008-2009 school year, eight teachers at Goshen High School participated in independent action research studies regarding the extent to which a six step approach to direct vocabulary…

Objective: This systematic review examined the effectiveness of school social work practices using meta-analytic techniques. Method: Hierarchical linear modeling software was used to calculate overall effect size estimates as well as test for between-study variability. Results: A total of 21 studies were included in the final analysis.…

Blanton and Jaccard questioned the 4-test regression method used by Greenwald et al. to test a pure multiplicative theory. The present authors address Blanton and Jaccard's concerns with a combination of simulations and meta-analysis. Simulations show that (a) Blanton and Jaccard's preferred simultaneous regression method has a severe power loss…

The authors performed a meta-analysis of the distributed practice effect to illuminate the effects of temporal variables that have been neglected in previous reviews. This review found 839 assessments of distributed practice in 317 experiments located in 184 articles. Effects of spacing (consecutive massed presentations vs. spaced learning…

Using computer simulation, the authors assessed the accuracy of J. E. Hunter, F. L. Schmidt, and H. Le's (2006) procedure for correcting for indirect range restriction, the most common type of range restriction, in comparison with the conventional practice of applying the Thorndike Case II correction for direct range restriction. Hunter et…

This paper discusses the fact that reliability is about scores and not tests and how reliability limits effect sizes. The paper also explores the classical reliability coefficients of stability, equivalence, and internal consistency. Stability is concerned with how stable test scores will be over time, while equivalence addresses the relationship…

Meta-analysis does not solve all the problems encountered in qualitative research reviews, but it holds out some hope for increasing the reliability and dependability of a reviewer's conclusions. Several developments in meta-analysis are cause for optimism. First, different meta-analysts are doing work in the same areas, leading to increased…

Using enrollment decline cases for data, the case survey method analyzes the content of case studies, thus allowing data from various cases to be aggregated and researchers to overcome constraints on data collection. The analyst uses six steps in this method in reviewing the case literature: (1) definition of the unit of analysis, (2)…

The most important problem in psychology and the social sciences today is the failure to produce cumulative knowledge. This situation has led many to conclude that cumulative knowledge and general principles and theories may be impossible to establish in psychology, a conclusion suggesting that psychology can never be a science--only at best a…

Two new methods for constructing a credibility interval (CI)--an interval containing a specified proportion of true validity description--are discussed, from a frequentist perspective. Tolerance intervals, unlike the current method of constructing the CI, have performance characteristics across repeated applications and may be useful in validity…

The reviewer has rich praise for this book and suggests that for readers not familiar with the topic of research synthesis this should be the first book they read.