Beyond the Timed Up and Go: Dual-Task Gait Assessments Improve Fall Risk Detection and Reflect Real-World Mobility in Multiple Sclerosis

Background: Falls are common among individuals with multiple sclerosis (MS), yet standard clinical mobility assessments—such as the Timed Up and Go (TUG)—may not fully capture the complexities of real-world ambulation, leading to suboptimal fall identification. There is a critical need to evaluate the ecological validity of these assessments and identify alternative tests that better reflect real-world mobility and more accurately detect falls. This study examined the ecological validity of the TUG and novel dual-task clinical assessments by comparing laboratory-based gait metrics to community ambulation in individuals with MS and evaluated their ability to identify fallers. Methods: Twenty-seven individuals with MS (age 59.11 ± 10.57) completed the TUG test and three novel dual-task mobility assessments (TUG-extended, 25-foot walk and turn, and Figure 8 walk), each performed concurrently with a phonemic verbal fluency task. After lab assessments, the participants wore accelerometers for three consecutive days. Gait speed and stride regularity data was collected during both the in-lab clinical assessments and identified walking bouts in the community. The participants were stratified as fallers or non-fallers based on self-reported fall history over the previous six months. Findings: Significant differences were observed between the TUG and real-world ambulation for both gait speed (p < 0.01) and stride regularity (p = 0.04). No significant differences were found in gait metrics between real-world ambulation and both the 25-foot walk and turn and TUG-extended. Intraclass correlation coefficient analysis demonstrated good agreement between the 25-foot walk and turn and real-world ambulation for both gait speed (ICC = 0.75) and stride regularity (ICC = 0.81). When comparing the TUG to real-world ambulation, moderate agreement was observed for gait speed (ICC = 0.56) and poor agreement for stride regularity (ICC = 0.41). The 25-foot walk and turn exhibited superior predictive ability of fall status (AUC = 0.76) compared to the TUG (AUC = 0.67). Conclusions: The 25-foot walk and turn demonstrated strong ecological validity. It also exhibited superior predictive ability of fall status compared to the TUG. These findings support the 25-foot walk and turn as a promising tool for assessing mobility and fall risk in MS, warranting further study.