The Psychometric Evaluation of Somatic Symptom Scale-۸ in Patients With Major Depressive Disorder

Objective: Somatic Symptom Disorder (SSD) is characterized by somatic symptoms that are very distressing or cause considerable functional disability. SSD is associated with various medical and psychiatric conditions and imposes high costs on the health care system. Therefore, early diagnosis and treatment of SSD are crucial. The somatic symptom scale-۸ (SSS-۸) is a valuable and brief self-report questionnaire to assess somatic symptom burden. The current study determined the psychometric properties of the Persian version of SSS-۸ in depressed samples. Methods: The study data were collected from a clinical setting with individuals diagnosed with major depressive disorder (MDD, n=۱۲۲). The convergent validity of SSS-۸ was examined by assessing its correlation with the hospital anxiety and depression scale (HADS), the Whiteley index (WI-۱۴), and somatic symptom disorder-B criteria scale (SSD-۱۲) questionnaires. Results: The Cronbach α results confirmed the reliability of SSS-۸. Reliability assessment with test-retest showed excellent reliability for scale. The confirmatory factor analysis also approved the SSS-۸ single-factor structure. The results of construct validity analysis of the questionnaire showed that SSS-۸ has a positive and significant relationship with depression, anxiety, WI, and SSS-۱۲. Conclusion: The Persian version of the SSS-۸ is an ۸-item self-report questionnaire that health professionals and researchers can use to assess and screen somatic symptoms in individuals diagnosed with MDD.

کلیدواژه ها:

Somatic symptom disorder ، Major Depressive Disorder ، Somatic symptom scale-۸ ، Validation ، Psychometrics