Further Validity of the Short Version of the Activities-Specific Balance Confidence Scale in Patients with Multiple Sclerosis

INTRODUCTION: There is scarce data on the utility of the short version of the Activities-specific Balance Confidence Scale in persons with multiple sclerosis (pwMS). Thus, this study aimed to expand the validity of the ABC-6 scale and compare it with the original version of the 16-item ABC scale (ABC-16) in pwMS.
METHODS: In total, 156 patients were included (median age: 35 years, 73.1% female and 26.9% male) in this study. The ABC-16 and ABC-6, timed up-and-go test (TUG), TUG-cognitive, six-minute walk test, timed 25-foot walk, MS walking scale, single-leg stance test, modified fatigue impact scale (MFIS), brief international cognitive assessment for multiple sclerosis, Beck depression inventory-II (BDI-II), and epworth sleepiness scale (ESS) were assessed. Validity was assessed in terms of criterion, convergent, discriminant, and known-group validity.
RESULTS: The correlation coefficient between the ABC-6 and ABC-16 was 0.974 (p<0.001). The ABC-16 and ABC-6 were strongly correlated with measures of the expanded disability status scale, all walking and balance tests, and physical and psychosocial subscores of MFIS (rs =-0.520 to -0.811, p<0.05). Moderate correlations were found with a cognitive subscore of fatigue, cognitive processing speed, visuospatial memory, and BDI-II (rs =-0.321 to -0.446, p<0.05). Low correlations were found in verbal memory and ESS scores (rs =-0.160 to -0.246, p<0.05). PwMS with a moderatesevere disability had significantly lower ABC-6 scores than that of patients with mild disability (p<0.001).
DISCUSSION AND CONCLUSION: The ABC-6 demonstrated high validity for measuring balance confidence in pwMS. Our findings strengthen the clinical utility of the ABC-6 in pwMS.