Validity and reliability of the unsupported upper-limb exercise test in individuals with rheumatoid arthritis

Abstract

Background: Rheumatoid arthritis (RA) is a chronic disease which affects the performance of the upper extremities. There is no method to evaluate the specific upper extremity endurance of individuals with this disease. The unsupported upper-limb exercise test (UULEX) is a performance test that evaluates upper extremity performance (functionality and endurance).

Aim: The aim of this study was to examine the reliability and validity of UULEX and the minimal detectable change (MDC) in individuals with RA.

Methods and materials: The study included 71 patients (15 male, 56 female) with a mean age of 52.15 ± 10.11 years. The intraclass correlation coefficient (ICC) was used to assess the reliability of UULEX. MDC estimates were calculated using baseline data. Correlations of UULEX with the Disability of Arm, Shoulder and Hand Questionnaire (DASH), Health Assessment Questionnaire (HAQ), 30-second push-up test and 6 pegboard ring test (6PBRT) were assessed for concurrent validity.

Results: The level, weight and duration scores of the UULEX test were found to be excellent for intra-rater reliability (ICC = 0.922, 0.960, 0.958). Intra-rater MDC values were determined to be 0.35, 2.04, and 0.80 seconds, respectively. Moderate-excellent correlations were found between UULEX and DASH, HAQ, 30-second push-up test and 6PBRT (P < .05).

Conclusion: The results of this study showed that UULEX test is a valid and reliable method for the assessment of upper extremity performance in individuals with RA.

Keywords: reliability; rheumatoid arthritis; unsupported upper-limb exercise test; upper extremity; validity.