Reliability and validity of the 6-minute pegboard and ring test for functional exercise capacity in patients with breast cancer

Abstract

ABSTRACT Background Chronic pain, sensory disturbances, and lymphedema are frequent after breast cancer, leading to arm dysfunction. There is a need for objective performance-based clinical exercise tests for the upper extremity in patients with breast cancer. Objective The aim of this study was to evaluate the validity and reliability of the 6-minute pegboard and ring test (6PBRT) in breast cancer survivors. Methods Forty-eight women with breast cancer (mean age = 55.40 ± 10.40 years) were included. All patients performed 6PBRT on the first day and one week later to investigate the test-retest reliability of the 6PBRT, and intraclass correlation coefficients (ICC) were calculated. The peak workload (Wpeak) and oxygen consumption level (VO2peak) during the arm ergometer test were used as outcomes for the criterion validity of the 6PBRT. Results The 6PBRT showed good test – retest reliability with an ICC1,2 value of 0.871 [95% confidence interval (CI) 0.769–0.928]. The first 6PBRT score was very strongly correlated with the second test score (r = 0.866, p < .001). The 6PBRT score was significantly correlated with VO2peak (r = 0.634, p < .001), and Wpeak (r = 0.546, p < .001). While the 6PBRT score had less effect on VO2peak, the determination of VO2peak in the model was very good (R2 = 0.832). Conclusion The 6PBRT has good test-retest reliability and is a valid test in individuals with breast cancer. These findings suggest that 6PBRT is a practical, useful, valid and reliable assessment tool for determining functional arm exercise capacity in patients with breast cancer.