Randomized controlled trials have proliferated in education, in part because they provide an unbiased estimator for the causal impact of interventions. It is increasingly recognized that many such trials in education have low power to detect an effect if indeed there is one. However, it is less well known that low powered trials tend to…

Using the Hartung-Knapp method and 95% prediction intervals (PIs) in random-effects meta-analyses is recommended by experts but rarely applied. Therefore, we aimed to reevaluate statistically significant meta-analyses using the Hartung-Knapp method and 95% PIs. In this methodological study, three databases were searched from January 2010 to July…

Early intervention efforts have been effective in reducing disruptive behaviors and the probability of poor developmental outcomes. Early interventions include common practice elements to improve social functioning and decrease problem behaviors that disrupt the teaching-learning process. The First Step Next intervention has been well validated…

The What Works Clearinghouse (WWC) is an initiative of the U.S. Department of Education's Institute of Education Sciences (IES), which was established under the Education Sciences Reform Act of 2002. It is an important part of IES's strategy to use rigorous and relevant research, evaluation, and statistics to improve the nation's education system.…

Large-scale randomized studies provide the best means of evaluating practical, replicable approaches to improving educational outcomes. This article discusses the advantages, problems, and pitfalls of these evaluations, focusing on alternative methods of randomization, recruitment, ensuring high-quality implementation, dealing with attrition, and…

Despite recent emphasis on the use of randomized control trials (RCTs) for evaluating education interventions, in most areas of education research, observational methods remain the dominant approach for assessing program effects. Over the last three decades, the within-study comparison (WSC) design has emerged as a method for evaluating the…

The purpose of this study was to develop and investigate an employer-based 9-month intervention for high school youth with autism spectrum disorder to learn job skills and acquire employment. The intervention modified a program titled Project SEARCH and incorporated the use of applied behavior analysis to develop Project SEARCH plus Autism…

The What Works Clearinghouse (WWC) systematic review process is the basis of many of its products, enabling the WWC to use consistent, objective, and transparent standards and procedures in its reviews, while also ensuring comprehensive coverage of the relevant literature. The WWC systematic review process consists of five steps: (1) Developing…

This multiyear scale-up effectiveness study of Open Court Reading (OCR) involved approximately 4,500 students and more than 1,000 teachers per year in Grades K-5 from 49 elementary schools in seven districts across the country. Using a school-level cluster randomized trial design, we assessed the implementation and effectiveness of Open Court…

In this longitudinal study, the cross-language transfer from second language (L2) to first language (L1) was examined among Spanish-speaking English-language learners in an English intervention (Grades 1-3) in the southwest United States. Path analysis revealed statistically significant transfers (ps < 0.05) for the treatment group from English…

In a cluster-randomized study, we investigate the impact of an argument-based approach to teaching science in elementary school on science learning and critical thinking skills. Forty-eight schools participated in the study, with data on 9,963 students across the 2 years of the intervention. Annual standardized tests assessing science content…

Background: Adapted parenting support may alleviate the high levels of parenting stress experienced by many parents with intellectual disabilities. Methods: Parents with mild intellectual disabilities or borderline intellectual functioning were randomized to experimental (n = 43) and control (n = 42) conditions. Parents in both groups received…

The Louisiana Scholarship Program (LSP) offers publicly funded vouchers to students in low-performing schools with family income no greater than 250% of the poverty line, allowing them to enroll in participating private schools. Initially established in 2008 as a pilot program in New Orleans, the LSP was expanded statewide in 2012. This article…

This study evaluated two 20-week reading interventions for pupils entering secondary school with reading difficulties. The interventions were delivered by trained teaching assistants (three 35-min sessions per week). 287 pupils (ages 11-13) from 27 schools were randomly allocated to three groups: reading intervention (targeting word recognition…

The purposes of this study were to (a) examine the degree to which teachers used linguistically responsive practices to support the language and literacy development of Spanish-speaking Dual Language Learners (DLL) and (b) to investigate the associations between these practices and select teacher-level factors. The sample consisted of 72 preschool…