Reliability and Validity of the Dissociative Experiences Scale Among South Korean Patients With Schizophrenia.
The Dissociative Experiences Scale (DES) is the most widely used self-report tool for use with the general population and various clinical entities, including those with schizophrenia. This preliminary study tested the reliability of the DES, especially temporal stability and validity, in patients diagnosed with schizophrenia receiving inpatient or outpatient treatment. The DES was administered at a university-affiliated training hospital in South Korea to a total of 68 patients (39 inpatients and 29 outpatients) whose diagnosis of schizophrenia was confirmed using the Structured Clinical Interview for DSM-IV Axis Disorders. Internal consistency, 4-week test-retest reliability, and validity were calculated. Participants also completed the Childhood Trauma Questionnaire, the Beck Depression Inventory, and the Symptom Checklist-Posttraumatic Stress Disorder Scale. Four-week test-retest reliability was moderate (r = .69) and internal consistency was good (Cronbach's α = .95). Total score on the DES was correlated with childhood trauma (r = .69, p < .001), posttraumatic symptoms (r = .50, p < .001), and depression (r = .52, p < .001), demonstrating the convergent validity of the scale. Our study confirms the psychometric soundness of the DES among patients with schizophrenia after the acute stage of illness (e.g., 3 weeks after admission), supporting use of the scale for screening and evaluating dissociative symptoms within this population.