Psychometric testing of the British English Workplace Activity Limitations Scale in four rheumatic and musculoskeletal conditions

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

doi:10.1093/rap/rkad028

Psychometric testing of the British English Workplace Activity Limitations Scale in four rheumatic and musculoskeletal conditions

Rheumatol Adv Pract. 2023 Mar 10;7(1):rkad028. doi: 10.1093/rap/rkad028. eCollection 2023.

Authors

Alison Hammond¹, Alan Tennant², Angela Ching¹, Jennifer Parker¹, Yeliz Prior¹, Monique A M Gignac^{3

4}, Suzanne M M Verstappen^{5

6

7}, Rachel O'Brien⁸

Affiliations

¹ Centre for Human Movement and Rehabilitation, School of Health and Society, University of Salford, Salford, UK.
² Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK.
³ Institute of Work and Health, Toronto, ON, Canada.
⁴ Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada.
⁵ Centre for Epidemiology Versus Arthritis, Centre for Musculoskeletal Research, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
⁶ Manchester Academic Health Science Centre, Manchester, UK.
⁷ NIHR Manchester Biomedical Research Centre, Manchester University NHS Foundation Trust, Manchester, UK.
⁸ College of Health, Well Being and Life Sciences, Sheffield Hallam University, Sheffield, UK.

Abstract

Objectives: The aims were to validate a British English version of the Workplace Activity Limitations Scale (WALS) linguistically, then test this psychometrically in RA, axial spondyloarthritis (axSpA), OA and FM.

Methods: The WALS was forward translated, reviewed by an expert panel, and cognitive debriefing interviews were conducted. Participants completed a postal questionnaire booklet. Construct (structural) 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: Minor wording changes were made to the WALS, then 831 employed participants completed questionnaires: 267 men and 564 women; 53.5 (s.d. 8.9) years of age; with condition duration 7.7 (s.d. 8.0) years. The WALS satisfied Rasch model requirements, and a WALS Rasch transformation table was created. Concurrent validity was strong with the WLQ-25 (RA r _s = 0.78; axSpA r _s = 0.83; OA r _s = 0.63; FM r _s = 0.64). Internal consistency was consistent with group use (α = 0.80-0.87). Test-retest reliability was excellent, with intraclass correlation coefficient (2,1) at ≥0.90.

Conclusion: A reliable, valid British English version of the WALS is now available for use in the UK.

Keywords: arthritis; musculoskeletal; patient-reported outcomes; rehabilitation; work; work rehabilitation.