Measuring UDL in the classroom: reliability and consistency of the Italian and French versions of the UDL Observation Measurement Tool

Given the increasing heterogeneity of school classrooms, education systems must design learning environments that are both accessible and inclusive. Universal Design for Learning (UDL) provides a comprehensive theoretical and practical framework that aims at ensuring equal opportunities for participation and learning. Although the UDL approach is increasingly adopted across European contexts, there remains a scarcity of effective tools to evaluate its implementation. This study examines the reliability and inter-rater consistency of the Italian and French versions of the UDL Observation Measurement Tool (UDL-OMT). To this end, 29 video-recorded lessons from inclusive and specialized classrooms in Switzerland were analyzed by both UDL expert researchers and trainee students. Consistent with findings from the original English version, the results confirm the reliability of the translated tools and the robustness of evaluations, even when conducted by non-expert observers. These findings support the use of the UDL-OMT as a valuable instrument for research, professional development, and self-assessment across diverse educational settings. The article concludes by discussing key practical and epistemological implications, study limitations, and future directions for the tool’s development.