Development of an unsupported arm exercise test in patients with chronic obstructive pulmonary disease

BACKGROUND: Unsupported arm exercise tests have been used to evaluate the effects of pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD), but the reliability and validity of these tests are not established. OBJECTIVE: We evaluated the test-retest reliability and validity of a 6-minute pegboard and ring test (PBRT) in 27 outpatients with COPD and 30 age-matched controls. METHODS: We evaluated a 6-minute PBRT, subject demographics, pulmonary function and disease-specific quality of life questionnaire, and the Pulmonary Functional Status Dyspnea Questionnaire- Modified version in 27 patients with COPD. RESULTS: Highly significant correlation coefficients (r = .91, P < .001) were found between test and retest of PBRT scores. Statistically significant correlation coefficients were found between PBRT scores and pulmonary function tests such as FEV1% pred and FVC% pred, and activity domain and subdomain of Pulmonary Functional Status Dyspnea Questionnaire-Modified (P ≤ .045). In addition, PBRT scores of healthy subjects were significantly higher than those of COPD subjects (P < .001), and were inversely related to age (P = .031). The FEV1% predicted and gender together accounted for 50% of the variance in the PBRT scores of patients with COPD. CONCLUSION: PBRT is a reliable and valid method to assess unsupported arm exercise endurance in patients with COPD.