Linguistic validation, validity, and reliability of the British English version of the Workplace Activity Limitations Scale in employed people with rheumatoid arthritis, ankylosing spondyloarthritis, osteoarthritis and fibromyalgia .

Hammond, Alison; Tennant, Alan; Ching, Angela; Parker, Jennifer; Prior, Yeliz; Gignac, Monique; Verstappen, Suzanne; O'Brien, Rachel

Abstract

Purpose: The Workplace Activity Limitations Scale (WALS) is a patient reported outcome measure of work ability developed in Canada for use in arthritis. The aims of this study were to linguistically validate a British English version of the WALS, and then psychometrically test this in rheumatoid arthritis (RA), ankylosing spondyloarthritis (AS), osteoarthritis (OA) and fibromyalgia (FM).

Methods: Phase 1: The WALS was forward translated, reviewed by an expert panel and cognitive debriefing interviews conducted. Phase 2: Participants completed a postal questionnaire booklet. Construct validity was examined by fit to the Rasch measurement model. Concurrent validity included testing between the WALS and the Work Limitations Questionnaire-25 (WLQ-25). Two weeks later, participants were mailed a second questionnaire booklet for test-retest reliability.

Results: Phase 1: Minor wording changes were made. Phase 2: 831 employed participants completed questionnaires: 267 men; 564 women; 53.5 (SD 8.9) years of age; with condition duration 7.7 (SD 8.0) years. The WALS satisfied Rasch model requirements when implemented in a bi-actor equivalent solution. A WALS Rasch transformation table was created. Concurrent validity was strong with the: WLQ-25 (RA rs = 0.78; AS rs = 0.83; OA rs = 0.63; FM rs = 0.64). Internal consistency was consistent with group use (α = 0.80 to 0.87). Test-retest reliability was excellent (ICC (2,1) at 0.90 or above.

Conclusions: A reliable, valid British English version of the WALS is now available for use in the United Kingdom.

Citation

Hammond, A., Tennant, A., Ching, A., Parker, J., Prior, Y., Gignac, M., …O'Brien, R. Linguistic validation, validity, and reliability of the British English version of the Workplace Activity Limitations Scale in employed people with rheumatoid arthritis, ankylosing spondyloarthritis, osteoarthritis and fibromyalgia

• Working Paper Type: Working Paper
• Deposit Date: Aug 7, 2024
• Publicly Available Date: Aug 15, 2024