Cultural adaptation and validation of the Chinese version of the Fatigue Severity Scale in patients with major depressive disorder and nondepressive people

The aims of the study were to adapt the Fatigue Severity Scale to Chinese conditions and assess the psychometric properties of the Chinese version in patients with major depressive disorder (MDD) and nondepressive people. A total of 101 patients with MDD and 94 nondepressive persons were included in this study. A forward and backward translation procedure was performed for developing a culturally acceptable Chinese version of the Fatigue Severity Scale (CFSS). Validity was assessed according to construct validity, internal consistency, concurrent validity, divergent validity, and contrasted-group validity. The CFSS exhibited a one-factor structure in patients with MDD and the nondepressive participants. A 7-item version of CFSS and an 8-item version of the CFSS demonstrated better model fit than the original 9-item version in the patients with MDD and the nondepressive participants, respectively. In both participant groups, internal consistency values were within acceptable ranges. In addition, concurrent validity and divergent validity were confirmed in both groups. The average CFSS score of patients with MDD was significantly higher than that of the nondepressive participants. The 9-item CFSS is a valid instrument for assessing fatigue-related impairment in Chinese-speaking patients with MDD. However, the two reduced-item CFSS versions showed better psychometric properties than the original version in the patients with MDD and the nondepressive participants.