Validity and reliability of four clinical gait measures in patients with multiple sclerosis

Abstract

Background: The gold standards for assessing ambulation are the Expanded Disability Status Scale (EDSS) and the Timed 25-Foot Walk (T25FW) test. In relation with these measures, we assessed the reliability and validity of four clinical gait measures: the Timed Up and Go (TUG) test, the Dynamic Gait Index (DGI), the 2-Minute Walk Test (2MWT), and the 6-Minute Walk Test (6MWT). Patient self-report of gait was also assessed using the 12-item Multiple Sclerosis Walking Scale (MSWS-12). Methods: Individuals 20 years or older with a diagnosis of multiple sclerosis (MS) and an EDSS score of 2.0 to 6.5 completed the MSWS-12, T25FW test, TUG test, DGI, 2MWT, and 6MWT. All the tests were repeated 2 weeks later at the same time of day to establish their reliability and concurrent validity. Predictive validity was established using the EDSS. Results: Forty-two patients with MS were included. All measures showed high test-retest reliability. The TUG test, 2MWT, and 6MWT were significantly correlated with the T25FW test (Spearman ρ = -0.902, -0.919, and -0.905, respectively). The EDSS was also significantly correlated with all the walking tests. The MSWS-12 demonstrated the highest correlation to the EDSS (ρ = 0.788). Conclusions: The TUG test, the DGI, the 2MWT, and the 6MWT exhibited strong psychometric properties and were found to be significant predictors of the EDSS score. Use of these tests to prospectively monitor the effects of medical and rehabilitation treatment should be considered in the comprehensive care of patients with MS.