In intervention studies, high rates of "implementation fidelity" are important markers of a study's success; however, the definition of implementation fidelity is both complex and dynamic. In this synthesis, we examined the dimensions of implementation fidelity measured and reported in 99 studies in which researchers utilized a…

High-quality Tier 1 instruction is frequently conceptualized as the "foundation" for other tiers of intervention within multitiered systems of support (MTSS) models. However, the vast majority of Tier 2 intervention studies do not account for Tier 1 variables when examining intervention effectiveness. The purpose of this study was to…

Teachers' implementation of differentiated supplemental instruction is critical to help students with or at risk for reading-related disabilities acquire early reading and vocabulary skills. This study represents an initial investigation of whether classroom teachers' intervention fidelity (exposure, adherence, and quality) of targeted reading…

Data from a small randomized control trial of teachers' use of Data-Based Instruction (DBI) for early writing were analyzed to determine the influence of teacher knowledge, skills, and treatment fidelity on student Curriculum-Based Measurement (CBM) slope. Participants included 11 elementary grade teachers who delivered intensive intervention in…

This study examines the interaction between the fidelity of implementation of a set of research-based strategies--Collaborative Strategic Reading (CSR)--and outcomes for students with mild to moderate disabilities using data from two nonoverlapping studies in middle school language arts and reading classrooms (Study 1) and middle school social…