Experimental and quasi-experimental designs are used in educational research to establish causality and develop effective practices. These research designs rely on a counterfactual model that, in simple form, calls for a comparison between a treatment group and a control group. Developers of educational practices often assume that the population…

In a sample of 195 first graders selected for poor reading performance, the authors explored four cognitive predictors of later reading comprehension and reading disability (RD) status. In fall of first grade, the authors measured the children's phonological processing, rapid automatized naming (RAN), oral language comprehension, and nonverbal…

Successful implementation of evidence-based educational practices at scale is of great importance but has presented significant challenges. In this article, the authors address the following questions: How does the level of on-site technical assistance affect student outcomes? Do teachers' fidelity of treatment implementation and their perceptions…