Servant Leadership in Higher Education: A Graded Response Model Approach to Item Response Theory Analysis

Given the limited number of servant leadership (SL) applications in higher education research, this study aims to provide higher education researchers with a sound and validated scale to measure SL in academic settings. More specifically, it evaluates the psychometric properties of the seven-item SL scale (SL-7) developed by Liden and colleagues. For this purpose, we collected data from lecturers in Malaysia, conducted thorough data screening procedures followed by verifying the assumptions of item response theory (IRT) analysis. These procedures led to the exclusion of two items from the original scale. Next, we proceeded with graded response model (GRM) analysis and evaluated the discrimination parameters, difficulty thresholds, and the patterns of information provided by each item. Our analysis supports the conclusion that the resulting five-item validated scale effectively measures lecturers' SL behavior in applied higher education research. Finally, we discussed the theoretical and practical implications of our findings and provided recommendations for future SL research in academic landscapes.