Examining the role of treatment adherence and instructional quality in the context of a content-area reading instructional treatment for eighth graders

Relatively few reading intervention studies have investigated treatment fidelity data and the extent to which fidelity is associated with student outcomes. This study extends the extant research by examining treatment adherence and quality and the extent to which these components of treatment fidelity relate to posttest performance for eighth grade students who received a content-area reading treatment targeting improved content knowledge and reading comprehension. Data were analyzed to address the following questions: (1) Do treatment adherence and quality indicate a general factor of fidelity? (2) Do treatment adherence and quality predict greater performance in content acquisition and reading comprehension? (3) To what extent are the effects of treatment adherence and quality on student outcomes moderated by teacher’s classroom management performance and student characteristics (pretest reading performance level, limited English proficiency status, special education status, and gender)? Situated within a larger randomized controlled trial examining the effects of a content-area instructional program, this study used data from the subsample of students (n = 790) in classes randomly assigned to treatment. Results showed a general factor of fidelity did not sufficiently predict treatment adherence and quality. Treatment adherence and quality were significant, positive predictors of content knowledge performance, which indicates that increases in both dimensions of treatment fidelity were associated with improvements in content knowledge posttest performance. However, a significant interaction between treatment adherence and quality was present. Interaction plots revealed instructional quality led to greater levels of posttest performance for students in classrooms with high levels of instructional adherence; however, instructional quality was not strongly associated with posttest performance when instruction was implemented with low adherence. Results also showed instructional quality was a significant, positive predictor of performance on the ASK Reading Comprehension subtest. Moderator analyses revealed teachers’ classroom management and students’ pretest performance influenced the effects of treatment adherence and quality on student outcomes. These findings help to elucidate the conditions under which the PACT instructional treatment leads to improved outcomes and, more broadly, underscores the importance of examining dimensions of treatment fidelity and the interplay between treatment fidelity dimensions and other teacher- and student-level characteristics when interpreting treatment effects.