The 6-Minute Pegboard and Ring Test (6PBRT) for Evaluation of Upper Limbs Functional Capacity in Hemodialysis Patients: A Validation Study.

Purpose: To verify the 6-minute pegboard and ring test (6PBRT) validity for functional evaluation in hemodialysis patients and upper limb (UL) functional capacity by the 6PBRT. Method: In a cross-sectional study, patients on hemodialysis three times a week for at least 6 months performed the 6PBRT as well as handgrip strength and endurance. Health-related quality of life (HRQoL) by KDQOL-SF questionnaire, Human Activities Profile (HAP), and level of social participation were also evaluated. Convergent validity was verified by correlation analysis. Results: Thirty-seven individuals were evaluated, predominantly adult males (67.6%). The mean age was 50.1 (SD 16.4) years old. The average number of rings moved during the 6PBRT was 306.2 (SD 68.2). The 6PBRT correlated with handgrip strength (r = 0.37; p = 0.025), the domain "Functional Capacity" (r = 0.49; p = 0.008) of the KDQOL-SF questionnaire, and with HAP score (r = 0.43; p = 0.01). There was no correlation between handgrip endurance (r = 0.18; p = 0.281) and social participation (r = -0.12; p = 0.48). Heart rate and dyspnea (modified Borg scale) increased by 13.3 bpm (95% CI: 9.8, 16.8) and 0.5 points (95% CI: 0.1, 0.9) during the 6PBRT. Conclusions: The 6PBRT is associated with UL strength, physical aspects related to HRQoL, and daily activity level, which accounts for its construct validity. Therefore, the test has potential value in the functional evaluation of the ULs in hemodialysis patients. However, in this population, the level of social participation seems to depend on other factors than the functional capacity of the UL itself.