An examination of psychometric properties of the Chinese version of the Positive and Negative Syndrome Scale for schizophrenia

BACKGROUND: The Positive and Negative Syndrome Scale (PANSS) is commonly used for assessment of severity of schizophrenic symptoms. In view of the ambivalent results over the factor structure of the scale, the present study aimed to examine the psychometric properties of PANSS by examining the consensus five-factor model by Wallwork in Chinese schizophrenic patients. METHODS: Participants were 146 Chinese patients with schizophrenia (mean age = 54.0 years, SD = 8.5) who resided in a rehabilitation hostel. They completed the Chinese PANSS, which is a 20-item, 7-point scale of psychiatric symptoms with five proposed factors. The five-factor structure of the PANSS and its convergent validity was evaluated via exploratory structural equation modelling using weighted least square estimator in Mplus 7.2. RESULTS: The five-factor consensus model fitted the data significantly better than a four-factor model (Δχ2(16) = 64.4, p < .01). Overall, the five-factor model provided an excellent model fit (χ2(100) = 119.8, p = .09, CFI = .99, TLI = .99, RMSEA = .04, SRMR = .03). The five factors were weakly to moderately correlated (r = .20 - .57, p < .05) except for positive-negative (r = .04), negative-cognitive (r = .19), and depression-cognitive (r = .03). All of the five factors showed satisfactory reliability. DISCUSSIONS: These results supported the use of the five-factor consensus model derived by Wallwork for PANSS in the Chinese context. Future studies should apply the PANSS in the Chinese patients with schizophrenia for assessment of psychiatric symptoms