Purpose: Children who do not develop early literacy skills, especially phonological awareness (PA) and alphabet knowledge, prior to kindergarten are at risk for reading difficulties. We investigated a supplemental curriculum with children demonstrating delays in these skills.Method: A cluster randomized design with 104 preschool-age children in 39…

Background: Cluster randomized experiments that assign intact groups such as schools or school districts to treatment conditions are increasingly common in educational research. Such experiments are inherently multilevel designs whose sensitivity (statistical power and precision of estimates) depends on the variance decomposition across levels.…

Purpose: The authors sought to determine whether a program of 5 weekly doses of milieu communication teaching (MCT) would yield improvements in children's communication and word use compared with a once-weekly delivery of the same treatment. Method: Sixty-four children with intellectual and communication delay were randomly assigned to receive…

This study examines how teacher and staff perceptions of the school environment correlate with student self-reports of bullying, aggression, victimization, and willingness to intervene in bullying incidents using multi-informant, multilevel modeling. Data were derived from 3,616 6th grade students across 36 middle schools in the Midwest, who…

Prior research has documented that classroom-level variables have a significant effect on student outcomes; however, previous findings have typically focused on average student outcomes and have only recently begun to use hierarchical linear modeling techniques. The present study aimed to investigate the effects of classroom-level variables on the…

Background: Cluster-randomized experiments that assign intact groups such as schools or school districts to treatment conditions are increasingly common in educational research. Such experiments are inherently multilevel designs whose sensitivity (statistical power and precision of estimates) depends on the variance decomposition across levels.…