Reliability and Validity of the Korean Version of the Somatic Symptom Disorder-B Criteria Scale in a Clinical Population

This study aimed to develop and validate the Korean version of the Somatic Symptom Disorder-B Criteria Scale (SSD-12) in outpatients at a psychiatric clinic and assess its diagnostic accuracy. A total of 207 patients completed SSD-12. For the diagnostic accuracy of SSD-12, the somatic symptom disorder (SSD) section of the structured clinical interview for DSM-5 disorders-research version (SCID-5-RV) was used. The SSD-12 construct and concurrent validity were assessed by examining the correlations with Generalized Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire-9 (PHQ-9), PHQ-15, 5-level EQ-5D version (EQ-5D-5L), and World Health Organization Quality of Life Brief Version (WHOQOL-BREF). The SSD-12 had excellent internal consistency (Cronbach α=0.90). Confirmatory factor analysis revealed good fit indices for a general factor model (comparative fit index [CFI]=0.92, Tucker-Lewis index [TLI]=0.88, root mean square error of approximation [RMSEA]=0.10; 95% confidence interval [CI], 0.08-0.11) and a three-factor model (CFI=0.94, TLI=0.91, RMSEA=0.08; 95% CI, 0.07-0.10). The total SSD-12 score was significantly correlated with anxiety (GAD-7: r=0.53, p