Professional development quality and instructional effectiveness: Testing the mediating role of teacher self-efficacy beliefs

The purpose of this study was to understand the mechanism linking the quality of professional development (PD) to instructional effectiveness by focusing on the mediating role of teachers' efficacy beliefs. Based on social cognitive theory and using the Teaching and Learning International Survey (TALIS) 2018 dataset, we confirmed that teacher self-efficacy beliefs significantly mediate the relation between PD quality and three indicators of instructional effectiveness - clarity of instruction, cognitive activation, and classroom management. Specifically, partial mediation was found for clarity of instruction and cognitive activation, while full mediation was found for classroom management. Our findings suggest that the relationship between PD quality and specific types of instructional practice is highly nuanced and mediated by teacher' self-efficacy beliefs. We discuss the implications of our findings for theory, future research, and practice.