Studying the Effectiveness of Team Teaching: A Systematic Review on the Conceptual and Methodological Credibility of Experimental Studies.

This article systematically reviews the conceptual and methodological credibility of experimental research on the effectiveness of team teaching, an instructional strategy where two or more educational professionals collaboratively teach a group of students. Analyzing 31 experimental studies published between 2000 and 2022, the review finds that while interest in experimental designs has increased—especially since 2015—many studies lack rigorous conceptual clarity and methodological quality, including insufficient sample sizes, inadequate reporting of measurement validity, and limited attention to contextual factors such as teacher characteristics and school environment. The review highlights variability in how team teaching is defined and implemented across studies, with frequent omission of key phases like evaluation/reflection and inconsistent use of team-teaching models. It concludes that future experimental research should adopt clearer conceptual frameworks and more rigorous methodological standards to provide policymakers and educators with reliable, evidence-based insights on team teaching's effectiveness.