Disability Measurement in Multiple Sclerosis: Beyond EDSS

Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system in which relapses and neurodegeneration lead to cumulative neurological decline. Historically, therapeutic development in MS has focused on relapse prevention, while disability progression has been evaluated using the Expanded Disability Status Scale (EDSS). However, EDSS is heavily weighted toward ambulation, and thus lacks sensitivity to less noticeable motor changes such as upper-limb dysfunction, and cognitive changes. Recently, the growing recognition that MS can progress independent of relapse activity has underscored the need for more precise, multidimensional assessment tools capable of capturing the full spectrum of MS-related impairment. Recent advances have introduced performance-based measures and composite functional outcomes integrating domains of ambulation, manual dexterity, cognition, and vision. These quantitative assessments provide objective and reproducible metrics of function and can detect subclinical progression earlier than conventional scales. As the focus of MS management shifts from relapse control to prevention of long-term disability, multidimensional functional assessment offers a practical and comprehensive approach for both clinical and research settings, with the potential to refine therapeutic decisions and improve patient outcomes.