Background: Axial spondyloarthritis (axSpA) is a chronic rheumatic disease, primarily characterized by inflammatory back pain and progressive functional limitations. Physical activity (PA) and exercise, including the four domains of cardiorespiratory fitness, muscle strength, flexibility, and neuromotor performance, play a central role in the disease management of axSpA [1,2]. The Inflammatory Arthritis Facilitators and Barriers (IFAB) Questionnaire [3] can be used to assess facilitators and barriers related to PA and exercise behaviour. According to EULAR recommendations, assessing both general and disease-specific barriers and facilitators to PA is crucial for developing tailored interventions to promote a physically active lifestyle [1]. Yet, no German version of the IFAB questionnaire was available.

Objectives: Therefore, this study aimed to translate and culturally adapt the IFAB into German (IFAB-G) and investigates its reliability among individuals with axSpA living in the German-speaking part of Switzerland.

Methods: The Cantonal Ethics Committee Zurich approved the study protocol (BASEC Nr. 2024-01274). The IFAB was initially translated using the TRAPD method (Translation, Review, Adjudication, Pretest, Documentation), involving experts and patients from Austria, Switzerland and Germany. Next, a cross-sectional study in a test-retest design was conducted, including statistical reliability analysis of internal consistency, the intraclass coefficient (ICC), the standard error of measurement (SEM), the minimal detectable change (MDC), floor and ceiling effects and the limits of agreement (LOA) for the IFAB-G. Data was collected via an online survey. Study data was collected and managed using the web-based software platform REDCap hosted at ZHAW

Results: The IFAB was successfully translated into the German language. Minor adjustments were required during translation and cultural adaptation. For test-retest reliability 55 individuals (mean age 57.5 (± 13.1) years, 25.5% male) with axSpA were statistically analyzed. The internal consistency was satisfactory, indicated by Cronbach alpha (α = 0.64). Relative test-retest reliability was calculated using ICC = 0.72 [95% CI 0.57; 0.83]), signifying a moderate level of agreement, with the SEM to be 8.56 while MDC was determined at 23.75. No floor or ceiling effects were observed in the global scores. The differences between baseline and retest total scores fell, apart from two, within the LOA.

Conclusions: This study demonstrates that the IFAB-G is a reliable instrument for identifying barriers and facilitators to PA, thereby contributing to the optimization of disease management in axSpA. By addressing psychological, social, disease-related, and environmental factors, the IFAB-G provides comprehensive insights into PA and exercise behaviour in individuals with axSpA.

REFERENCES: [1] Rausch Osthoff AK, et al (2025) DOI: 10.1016/j.ard.2025.06.788.

[2] Ramiro S,et al (2022) DOI: 10.1136/ard-2022-223296.

[3] Davergne T., et al (2020) DOI: 10.1007/s00296-020-04692-4.

Acknowledgments: NIL.

Disclosure of Interests: None declared.