Sustainable Digital Learning in Higher Education: Development of the Moodle-Based BirDeHa Usability Scale and Its Associations with Academic Locus of Control and Achievement Motivation

Learning management systems (LMSs) are increasingly recognized as tools for promoting sustainable education, yet the psychological mechanisms linking LMS usability to student motivation remain underexplored. This three-study research develops and validates the Moodle-based BirDeHa Usability Scale (BirDeHa-US) and examines academic locus of control as a mediator between LMS usability and achievement motivation. Study I (n = 2200) used exploratory factor analysis to establish a 19-item unifactorial structure explaining 76.55% of the variance. Study II (n = 3606) confirmed the factor structure via confirmatory factor analysis, established full measurement invariance across gender, and demonstrated high discriminatory power via IRT and strong criterion-related validity. Study III (n = 1076) tested mediation models, revealing that internal and external locus of control partially mediated the relationship between perceived LMS usability and achievement motivation. Specifically, higher perceived usability was positively associated with internal locus of control and negatively associated with external locus of control. These findings suggest that well-designed digital learning environments can foster autonomous motivational orientations conducive to sustained academic engagement.