Assessing Teacher Competency Disparities Through Rasch and DIF Analysis

Mapping disparities in teacher competencies is essential for advancing equitable education quality in Indonesia. This study investigates the psychometric quality of three teacher competency instruments—the Questionnaire on Teacher Interaction (QTI), Teacher Reflective Practice Questionnaire (TRPQ), and Teacher Knowledge Creation Questionnaire (TKCQ)—and examines competency disparities across teacher demographic groups with explicit attention to measurement fairness. A cross-sectional quantitative survey was conducted with 511 elementary and junior high school teachers in Gorontalo Province. Data were analyzed using the Rasch Measurement Model to evaluate model fit, item and person reliability, unidimensionality, rating scale functioning, and Differential Item Functioning (DIF). The results indicate that all three instruments demonstrated good overall fit to the Rasch model, with very high item reliability (≥0.97) and person reliability ranging from moderate (QTI = 0.68) to very good (TKCQ = 0.86). The rating scales functioned optimally, and item–person targeting was particularly strong for the QTI and TRPQ instruments. DIF analysis revealed meaningful disparities in teacher competencies associated with certification status, teaching experience, and school location, indicating structural inequities rather than measurement bias. These findings confirm the validity and fairness of the instruments and underscore the importance of Rasch–DIF-based analyses for diagnosing competency gaps. The study recommends the implementation of tiered, data-driven professional development (PD) programs to support equitable and targeted teacher competency enhancement.