Validity and reliability of the ten-item Connor-Davidson Resilience Scale (CD-RISC10) instrument in patients with axial spondyloarthritis (axSpA) in Singapore.

We aimed to assess the validity and reliability of the ten-item Connor-Davidson Resilience Scale (CD-RISC10) in patients with axial spondyloarthritis (axSpA) in Singapore. We used cross-sectional data from 108 patients with axSpA recruited from a dedicated axSpA clinic in a Singapore tertiary referral hospital from 2017 to 2018. Analyses were guided by the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) framework. Face validity was assessed through cognitive debriefing interviews (CDIs). Internal consistency was assessed through Cronbach's alpha. Test-retest reliability was assessed through intraclass correlation (ICC). Measurement error was assessed through smallest detectable change (SDC). Construct validity was assessed through six a priori hypotheses through correlation of the CD-RISC10 score with other patient-reported outcome measures. Structural validity was assessed using confirmatory factor analysis (CFA). Fit indices evaluated were root-mean-square error of approximation (RMSEA), comparative fit index (CFI), Tucker-Lewis index (TFI), and standardized root-mean-squared residual (SRMR). Ten patients completed the CDIs and face validity was supported. Among 108 patients (median age: 37(21-77), 81.5% males, 93.5% Chinese), the CD-RISC10 demonstrated good internal consistency (Cronbach's alpha = 0.94), and excellent test-retest reliability [ICC = 0.964 (95% CI 0.937-0.980)]. SDC was calculated as 1.88. Construct validity was established by meeting five out of the six a priori hypotheses. Structural validity was supported as CFA confirmed a one-factor model, with adequate fit statistics after adding three covariances (RMSEA = 0.077; CFI = 0.975; TLI = 0.964; SRMR = 0.036). This study supports the CD-RISC10 as a valid and reliable measure of resilience for use in patients with axSpA.