Abstract
Including students with disabilities requires schoolwide interventions that are implemented with fidelity (adherence). Collection of fidelity data may become problematic when multiple evidence-based treatments exist in one setting. To address concerns around efficiency of data collection, this study hypothesized that the three sampling approaches (proportional, consensus, stratified random) provided similar levels of agreement with an expert rater, thus warranting the differentiation in their applications based on the needs of the evaluators. Three high schools were randomly assigned to one of three sampling approaches (i.e. proportional, consensus, stratified random) to complete a fidelity measure for the implementation of a schoolwide inclusion approach. Based on the Median Test, each sampling approach did not differ significantly from the scores of an expert rater. The results indicate that schools may have some choice in the methods they use to sample their staff around the measurement of fidelity of implementation.