Validity and reliability of the Six-Minute Pegboard Ring Test for assessing functional capacity and upper limb function in persons with multiple sclerosis

Background: The timed walk test is essential for assessing the functional capacity of persons with multiple sclerosis (MS). When a decline in ambulation ability and loss of function in the later stages of MS is observed, it is imperative to utilize alternative methods for measuring functional capacity. Objective: To investigate the validity and reliability of the Six-Minute Pegboard Ring Test (6PBRT) in persons with MS. Methods: Forty-three persons with MS were included in this study. Disease severity was quantified using the Expanded Disability Status Scale (EDSS). The 6PBRT was employed to assess upper extremity function during exercise stress, and vital signs were monitored pre- and post-test. Muscle strength was measured using a digital dynamometer for shoulder flexor, shoulder abductor, and grip strength, in addition to a hand dynamometer. Manual dexterity was evaluated through the 9-Hole Peg Test (9HPT), and walking endurance was assessed using the 2-Minute Walk Test (2MWT). Test-retest reliability was computed using the intraclass correlation coefficient (ICC). Results: The ICC value for the 6PBRT was 0.96 (95% CI 0.92-0.97), indicating excellent test-retest reliability. Significant differences in vital signs were observed before and after conducting the 6PBRT (p p < 0.05). A strong negative correlation was found between the 6PBRT score and EDSS (r =-0.650, p < 0.001). The 9HPT of the dominant side demonstrated a moderate correlation with the 6PBRT score (r =-0.502, p = 0.001), whereas no significant correlation was shown between the non-dominant side 9HPT and the 6PBRT score (p > 0.05). Moreover, a positive moderate correlation was shown between the performance on the 2MWT and the 6PBRT score (r = 0.413, p = 0.006). However, no significant correlation was detected between the proximal muscle strength of the upper extremity, handgrip strength, and the 6PBRT score in individuals with multiple sclerosis (p > 0.05). Conclusion: The 6PBRT is a reliable and valid tool to evaluate upper extremity function and exercise capacity in persons with MS.