Reliability and validity of the Chinese version of the post-traumatic embitterment disorder self-rating scale (PTED-21) among inpatients in general hospital.

Abstract

Embitterment and in some cases also post-traumatic embitterment disorder (PTED) are relevant problem in the general population and even more so in psychiatric patients. PTED screening should be an essential component of routine mental health management, which can be done by the 21-item Post-traumatic Embitterment Disorder Self-Rating Scale (C-PTED-21), which measures the intensity of reactive stimulus bound embitterment. The PTED-21 German version was translated into Chinese, and 200 nonpsychiatric inpatients, reporting major negative life events, were recruited through convenience sampling to evaluate test performance. Ninety patients were selected for retest 2weeks later to examine scale reliability. Factor analysis was used to assess construct validity and receiving operating characteristic curve analysis based on the "PTED standardized diagnostic interview" to assess diagnostic utility. Correlations with depression, somatic symptom, and anxiety scales were examined to assess aggregate validity. The C-PTED-21 demonstrated high internal consistency (Cronbach's α=0.944) and good test-retest reliability (total score r=0.783, individual item r value range, 0.635-0.889). Factor analysis revealed three common factors consistent with PTED core features. Total C-PTED-21 score was strongly correlated with the score on the nine-item Patient Health Questionnaire depression scale (PHQ-9, r=0.735). Mean PTED-21 score ≥1.6 points distinguished clinical PTED as defined by diagnostic interview with 97.6% sensitivity and 90.5% specificity (AUC=0.988, 95%CI: 0.976-0.999). The results show that the C-PTED-21 can assess the severity of PTED with good reliability and validity.