Psychometric properties and socio-demographic correlates of the Connor-Davidson Resilience Scale in three large population-based cohorts including Danish and Icelandic adults.

Identifying specific factors affecting psychological resilience could be instrumental in developing new therapeutic strategies for improving and maintaining mental and physical health. To achieve this, an adequate measure of psychological resilience is essential. We studied the psychometric properties of the 10-item Connor-Davidson Resilience Scale (CD-RISC-10) across three population-based cohorts. The study included adult Danish individuals in the Danish Blood Donor Study (DBDS, N = 57,031), and the Icelandic cohorts Stress-And-Gene Analysis cohort (SAGA, N = 27,236), and COVID-19 National Resilience cohort (C19-Resilience, N = 20,373). Exploratory factor analysis revealed a consistent one-factor fit across cohorts. The scale demonstrated good internal consistency (Cronbach's alpha: 0.88-0.90) and longitudinal stability (Spearman correlation coefficients in DBDS: 0.71 across 1.5 years, 0.66 across two years). Mean CD-RISC-10 scores were consistent with previously reported scores in European populations. Lower scores were observed among participants with probable major depressive disorder, and higher scores were found with increasing age. Further evidence for construct validity was revealed as CD-RISC-10 scores moderated the association between financial trouble and depressive symptoms across all cohorts. Psychometric properties of the CD-RISC-10 were similar among women and men. Our findings support the use of the CD-RISC-10 as a reliable and valid unidimensional measure of psychological resilience in Danish and Icelandic populations.