In two-level designs, the total sample is a function of both the number of Level 2 clusters and the average number of Level 1 units per cluster. Traditional multilevel power calculations rely on either the arithmetic average or the harmonic mean when estimating the average number of Level 1 units across clusters of unbalanced size. The current…

Power in multilevel models remains an area of interest to both methodologists and substantive researchers. In two-level designs, the total sample is a function of both the number of level-2 (e.g., schools) clusters and the average number of level-1 (e.g., classrooms) units per cluster. Traditional multilevel power calculations rely on either the…

This study presents findings from a 58 high-school group-randomized controlled trial testing the effectiveness of training in a multitiered system of supports for behavior (MTSS-B) framework, which was leveraged to reduce students' risk for emotional and behavior disorders. The trial tested the impact of MTSS-B, which included (a) training in the…

There are several widely used Positive Behavioral Interventions and Supports (PBIS) implementation fidelity measures, including the Schoolwide Evaluation Tool (SET), but there is limited empirical investigation substantiating the association between specific fidelity cut point scores and student outcomes. This article examined different SET cut…

Cluster randomized experiments are now widely used to examine intervention effects in prevention science. It is meaningful to use empirical benchmarks for interpreting effect size in prevention science. The effect size (i.e., the standardized mean difference, calculated by the difference of the means between the treatment and control groups,…

Generalizability theory (GT) offers a useful framework for estimating the reliability of a measure while accounting for multiple sources of error variance. The purpose of this study was to use GT to examine multiple sources of variance in and the reliability of school-level teacher and high school student behaviors as observed using the tool,…

There is growing interest in the use of a multi-tiered system of supports framework to address issues related to school climate and bullying. Positive Behavioral Interventions and Supports (PBIS) is one such model that has received considerable attention; however, nearly all of the extant literature has focused on elementary and middle schools,…

Coaching models are increasingly used in schools to enhance fidelity and effectiveness of evidence-based interventions, yet little is known about the relationship between the coach and teacher (i.e., coach-teacher alliance), which may indirectly enhance teacher and student outcomes through improved implementation quality. There is also limited…