Examining fidelity reporting within studies of foundational reading interventions for elementary students with or at risk for dyslexia

Early access to evidence-based reading intervention improves outcomes for students with or at risk for reading difficulties. Additionally, teacher implementation of reading interventions plays a key role in the efficacy of reading interventions. Previous research suggests the influence of intervention implementation fidelity on student language and literacy outcomes is more significant for lower-performing students and students with disabilities, such as dyslexia. However, recent syntheses have suggested that less than half of reading intervention studies report treatment fidelity data. This meta-analysis examined fidelity reporting within reading intervention studies for students with or at risk for dyslexia in Grades K–5. We aimed to record the frequency and extent of fidelity reporting, explore associations between study or intervention features and fidelity reporting, and compare mean intervention effect sizes for studies reporting fidelity and those that did not. A total of 51 studies were included. Results indicated that 75% of studies reported fidelity data. Studies reporting fidelity primarily focused on adherence and dosage data with little to no information reported for other dimensions of fidelity (i.e., quality, responsiveness, differentiation). Suggestions for improving reporting of treatment fidelity data are discussed.