The Influence of Different Phrasing of the “Patient Global Assessment of Global Health” on the Patient’s Rating and Disease Activity Score in Ankylosing Spondylitis

Abstract

Objective: The standardized phrasing for the patient’s global assessment of general health (PtGA-GH) is not defined yet, and the phrasing of question could vary the patient’s response. This study aimed to evaluate whether different phrasings of the PtGA-GH affect the patient’s rating, and whether PtGA-GH and patient’s global assessment of disease activity (PtGA-DA) could be used interchangeability to calculate the Ankylosing Spondylitis Disease Activity Score (ASDAS) in ankylosing spondylitis (AS).

Methods: In this retrospective cross-sectional study, the patient’s perception of their own general health was evaluated with PtGA-GH question (PtGA-GHQ) and the third question of RAPID3 (RAPID3-Q3). A difference ≥1 between PtGA-GHQ and RAPID3-Q3 was considered discordance. Lin’s concordance coefficient (LCC) and Bland–Altman plots were used to determine the equivalence. The kappa (κ) statistics were used to evaluate the level of agreement in disease activity classification.

Results: Three-hundred twenty-one AS patients were included. Discordance was detected in 192 (59.8%) patients. Demographic and clinical characteristics were similar between concordant and discordant groups. In the sensitivity analysis, the number of discordant patients reduced to 91 (28.3%), but the patient’s characteristics remained similar between groups. The LCC of 0.792 and Bland–Altman’s limits of agreement of −4.169 to 3.172 indicated that PtGA-GHQ and RAPID3-Q3 are not interchangeable. The LCC was 0.750 for ASDAS-C-reactive protein (ASDAS-CRP) and RAPID3-Q3- based ASDAS-CRP, but the κ value was 0.190. The LCC was 0.982 for Ankylosing Spondylitis Disease Activity Score-erythrocyte sedimentation rate (ASDAS-ESR) and RAPID3-Q3-based ASDAS-ESR, and κ was 0.825 with 87.5% absolute agreement.

Conclusion: Different question patterns may not be used interchangeability as individual variables for AS activity assessment. The RAPID3-Q3 may be used to calculate ASDAS-ESR.

Cite this article as: Kaya MN, Tecer D, Ozgunen MS, Cinar M, Yılmaz S. The influence of different phrasing of the “patient global assessment of global health” on the patient’s rating and disease activity score in ankylosing spondylitis. Eur J Rheumatol. 2025, 12(3), 0133, doi: 10.5152/eurjrheum.2025.24133.