Psychometric Properties of the Chinese Version of the Clinically Useful Depression Outcome Scale for Patients with Major Depressive Disorder

Abstract

Objective: This study aimed to evaluate the psychometric properties of the Chinese version of the Clinically Useful Depression Outcome Scale (CUDOS). Methods: One hundred ninety patients with major depressive disorder (MDD) according to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria were recruited to the study. The English version of the CUDOS was translated into Chinese using a forward and backward translation method, which was according to the guidelines of adaptation and validation of instruments in cross-cultural health care research. The Chinese version of the CUDOS, the 17-item Hamilton Rating Scale for Depression (HRSD) and the improved Clinical Global Impression-Severity Scale (iCGI-S) were used to evaluate depressive symptoms in one hundred ninety patients with MDD. One week after the first evaluation, sixteen patients were selected randomly for a second assessment. Reliability and validity tests and receiver operating characteristic curves were performed. Results: The internal consistency of the CUDOS was 0.95, and the split-half reliability coefficient of the CUDOS was 0.92. The correlation coefficient of the retest in sixteen patients was 0.77 (P < 0.01). There was a significant difference in the total score of the Chinese version of the CUDOS between the different levels of depression severity groups (P < 0.01). The ability of the CUDOS to identify patients in remission was high (area under ROC curve= 0.97). A cut-off score of 14/15 yielded 90.20% sensitivity and 93.60% specificity when iCGI-S=1. Conclusion:The Chinese version of the CUDOS is valuable as a brief and reliable instrument to assess depressive symptoms and clinical outcome. The findings suggest that the optimal cut-off score to identify patients in remission was 14/15.

Rasch analysis of the Chinese version of the Clinically Useful Depression Outcome Scale in patients with major depressive disorder

“…However, the proportion of raw variance data, high disattenuated correlations and person correlations suggested that the Chinese version of CUDOS is a unidimensional contruct scale, which was consistent with previous studies by CTT [11,14]. Hence results in the current study supported a unidimensional construct the Chinese version of CUDOS.…”

“…Although the Chinese version of CUDOS has been validated in Chinese patients with MDD using CTT [14].…”

“…In the current study, depressive symptoms were assessed by the Chinese version of the CUDOS. Good reliability and validity of the scale have been demonstrated through traditional CTT [14].…”

“…In our previous study, we examined the psychometric properties of the Chinese version of CUDOS in patients with MDD using traditional Classical Test Theory (CTT), and demonstrated that the scale had good reliability and validity [14]. However, the results could not provide detailed information of individual item performance.…”

“…The CUDOS is also user-friendly, it has less burden of scale completion to patients so they were willing to complete it regularly [13]. The original English version of CUDOS has been translated into several languages and all of the previous studies have consistently demonstrated that the CUDOS showed excellent reliability and validity [14][15][16].…”