Negative symptoms are main predictive factors of schizophrenia disability and seriously affect the social function and quality of life of patients with schizophrenia. Therefore, the development and validation of negative symptoms of schizophrenia has been one of the prioritized areas for schizophrenia research. Recent theoretical and clinical findings suggest that negative symptoms can converge into two factors, namely the “motivation-anhedonia” and the “expression”. The Clinical Assessment Interview for Negative Symptoms (CAINS) was developed in accordance with this theoretical framework and has been validated with good psychometrics traits in Caucasian samples. However, very little is known about the clinical utility of the CAINS in the Chinese settings and it is still unclear whether the spectrum of the disorders could be effectively discriminated by CAINS.
To address these unresolved issues, Dr. Raymond Chan and his team from the Neuropsychology and Applied Cognitive Neuroscience (NACN) Laboratory, key Laboratory of Mental Health, Institute of Psychology, and Department of Psychology, University of Chinese Academy of Sciences have conducted two studies to examine the presentation of negative symptoms in schizophrenia, their non-psychotic first-degree relatives, and individuals with schizotypy using the Chinese version of CAINS.
In the first study, they administered the CAINS together with conventional clinical ratings on negative symptoms to 185 patients with schizophrenia and conducted confirmatory factory analysis to examine the latent structure of negative symptoms. Their findings showed there was a stable two-factor structure, namely “motivation-pleasure” and “expression”. Significant correlations were also found between these two factor subscores with negative symptoms captured by the conventional clinical ratings as well as the self-reported experience of pleasure.
Then, they further conducted an independent sample to explore the discrimination of the CAINS along the spectrum of the disorders. They administered the set of measures used in the first study to 44 patients with schizophrenia, 43 non-psychotic first-degree relatives, 37 individuals with schizotypy, and matched healthy controls. People with schizophrenia exhibited significantly higher CAINS subscale scores than first-degree relatives and controls. In addition, first-degree relatives had higher “motivation/pleasure” scores than controls. The subscale scores of individuals with social anhedonia were also significantly higher than healthy controls.
Taken together, the present findings suggested that the Chinese version of the CAINS demonstrated a robust two-factor structure of “amotivation-anhedonia” and “expression” factors of negative symptoms in schizophrenia. More importantly, the present study also showed that expressive deficits and amotivation-anhedonia are consistently present not only in the patients with schizophrenia but also non-psychotic first degree relatives and individuals with schizotypy, and even in non-clinical sample. The CAINS factor scores are sensitive to discriminate patients with schizophrenia, non-psychotic first-degree relatives, and individuals with schizotypy from healthy controls. These all support the Chinese version of the CAINS is an effective and valid clinical tool for assessing negative symptoms for schizophrenia, and even in other clinical groups exhibiting similar negative symptoms in the Chinese setting.
This study was supported by the National Science Fund China, National Key Research and Development Programme, the Beijing Training Project for the Leading Talents in Science and Technology, the Beijing Municipal Science & Technology Commission Grant, and the CAS/SAFEA International Partnership Programme for Creative Research Teams, and a grant from the key Laboratory of Mental Health, Institute of Psychology.
Xie, D. J., Shi, H. S., Lui, S. S. Y., Shi, C., Li, Y., Ho, K. K. Y., Hung, K. S. Y., Li, W. X., Yi, Z. H., Cheung, E. F. C., Kring, A. M., Chan, R. C. K*. (2018). Cross cultural validation and extension of the Clinical Assessment Interview for Negative Symptoms (CAINS) in the Chinese context: Evidence from a spectrum perspective. Schizophrenia Bulletin, https://doi.org/10.1093/schbul/sby013