POS0391 THE MSQUASH AS MEASUREMENT TOOL FOR DAILY PHYSICAL ACTIVITY: TRANSLATION AND CROSS-CULTURAL ADAPTATION INTO ENGLISH, FIELD-TESTING IN DIFFERENT RHEUMATIC DISEASES AND CLINICAL VALIDATION IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS
Authors: Y. M. Van der Kraan, L. S. Gensler, D. Paap, E. Thovmasyan, N. S. Ausma, H. Kokol, M. Carbo, K. De Leeuw, K. Van der Geest, H. Bootsma, J. P. L. Spoorenberg, S. Arends
Journal: Annals of the Rheumatic Diseases (2024)

<h3>Background:</h3> Regular physical activity can have beneficial effects on symptoms, functional status and general health in patients with rheumatic diseases. The modified Short QUestionnaire to Assess Health enhancing physical activity (mSQUASH) was developed and validated in Dutch axial spondyloarthritis (axSpA) patients.[1] The original SQUASH was developed for the general Dutch adult population. [2] The adaptations were focused on the structure of the SQUASH, modernization of examples and standardization of the response options. [1] Since adaptations of mSQUASH for axSpA were overall generic, we expect that the mSQUASH is more widely applicable and can also be used in patients with other rheumatic diseases. <h3>Objectives:</h3> To support world-wide distribution, applicability and comparability of measuring physical activity, our aim was to perform translation and cross-cultural adaptation of the mSQUASH into English, with field testing in other rheumatic diseases, and clinical validation of the mSQUASH in axSpA patients. <h3>Methods:</h3> The Dutch mSQUASH was translated into English according to the forward-backward Beaton protocol. For cross-cultural adaptation, semi-structured in-depth interviews were conducted in axSpA patients at the University of California, San Francisco (UCSF). To check its wider applicability, semi-structured, one-to-one, in-depth interviews were performed in patients with Sjögren's disease (SjD), systemic lupus erythematosus (SLE) and giant cell arteritis/polymyalgia rheumatica (GCA/PMR) at the University Medical Center Groningen. Clinical validation was performed in axSpA patients at UCSF. To assess construct validity, Spearman correlations were used to analyse the association between the mSQUASH and disease activity, physical function and QoL and disease-related health status. To assess test-retest reliability after 2 weeks, intra-class correlation coefficients (ICC) were calculated. Additionally, Bland-Altman analysis was conducted to determine the 95% limits of agreement (LOA) and to evaluate if systemic differences were present. To assess responsiveness after 3 months, standardized response means (SRM) were calculated stratified by Anchor method of self-reported improved, stable or worsened physical activity. <h3>Results:</h3> Translation and cross-cultural adaptation of the mSQUASH into English was successfully carried out in axSpA patients, which can serve as basis for other translations. Patients with axSpA (n=13), SjD (n=10), SLE (n=10) and GCA/PMR (n=10), included for the cognitive debriefing interviews, represented range of age, sex, educational level and disease severity. All patients (n=43) found the mSQUASH relevant and easy to complete. Only minor adaptations and clarifications were implemented. On average, it took participants 5 minutes to complete the mSQUASH. In total, 95 axSpA patients were included for clinical validation in the USA; median age 46 [38-54] years, 71% male, 80% was classified as radiographic axSpA, median time since diagnosis 12 [8-21] years and median ASDAS 1.4 [0.9-2.1]. As expected, fair correlations were found between the mSQUASH and BASDAI (ρ=-0.25), ASDAS (ρ=-0.31), BASFI (ρ=-0.37), ASQoL (ρ=-0.30) and ASAS-HI (ρ=-0.30). Test-retest reliability was very good for mSQUASH total score (ICC: 0.87). Bland-Altman plot revealed no systemic bias. The 95% LOA were wide, indicating that only large changes can be considered true changes. Responsiveness was moderate and corresponded to the direction of self-reported changes in physical activity (SRM: 0.72 for improved, 0.06 for stable, and -0.74 for decreased). <h3>Conclusion:</h3> The mSQUASH showed good linguistic and face validity according to field testing in axSpA patients from the USA and in patients with other rheumatic diseases in the Netherlands. Clinical validation confirmed good construct validity, test-retest reliability and responsiveness in axSpA patients. The mSQUASH and manual (including list of sports and activity codes, SPSS syntax and database template) can be provided at no additional costs. <h3>REFERENCES:</h3> [1] Carbo et al. Semin Arthritis Rheum. 2021;51(4):719-27. [2] Wendel-Vos et al. J Clin Epidemiol 2003;56(12):1163–9. <h3>Acknowledgements:</h3> The authors would like to thank the ASAS for granting the ASAS research fellowship to this study. <h3>Disclosure of Interests:</h3> <b>None declared.</b>