To the best of our knowledge, this study provided the first cross-cultural adaptation and validation data for the Chinese Mandarin version of KAST, which could be used as a primary assessment of schizophrenia knowledge. The English and Portuguese versions of KAST had been previously validated. Our results showed that the reliability and reproducibility of the Chinese Mandarin version of KAST were validated based on internal consistency, item analysis, and retest reliability. This study also analyzed sociodemographic and clinical factors associated with caregiver KAST scores. The results found gender, educational attainment, marital status, relationship, and occupational status, were each associated with KAST scores.
Our study found that the KAST has sound psychometric properties. We deleted question 17 because of different social backgrounds, patients and their families can obtain relevant information and support for schizophrenia from some formal and more official organizations such as the Chinese Medical Association and the CDC. The Chinese-version KAST had acceptable internal consistency (KR-20 reliability coefficient was 0.702) and reproducibility (intraclass correlation coefficient for retesting was 0.686) through standard translation and screening. Consistent with Compton et al. [10]and the Portuguese version of KAST[11], the original English version had a KR-20 reliability coefficient of 0.82. The Portuguese version had an intraclass correlation coefficient of 0.592 for retesting, both of which verified the validity and reliability of KAST.
In our study, items 2, 8, 9, and 16 were less than 50% correct regarding the etiology and symptoms of schizophrenia and atypical drugs used for treatment, indicating that they still have misconceptions about the etiology and symptoms of schizophrenia and lack of knowledge about the atypical drug " Quetiapine" used for treatment. In addition, perceiving the problem of schizophrenia etiology as non-biological may reflect the general health beliefs of the Chinese[18]; caregivers are more likely to attribute the etiology of schizophrenia to psychological or supernatural causes[19].
Multivariate regression results indicated that female caregivers had better knowledge of the illness (higher KAST scores) than males. This is consistent with previous findings, which suggested female caregivers gained higher levels of knowledge than male caregivers after participating in psychoeducation programs, but it may be related to the relatively higher educational attainment of women participating in psychoeducation[20]. Also, in our study, individuals with at least a university education had a higher level of knowledge about the disease compared to caregivers with a middle school education or below. This is consistent with the results of the English [10]and Portuguese[11] versions of the test while reinforcing, to some extent, the validity of the instrument's construct, theoretically, those college-educated individuals have higher levels of knowledge. Caregivers who are married or divorced or widowed tend to be older and may have a better understanding of the disease due to the longer time spent caring for the patient. For unemployed caregivers, they may also have a better understanding of the disease because they have lost their jobs and have more effort to care for the patient. Conversely, caregivers who are in other relationships such as siblings may also have a poorer understanding of the disease because they may be less close to the patient in comparison to parent or children.
This study is subject to several limitations. First, we selected participants from community health centers by convenience sampling, which may not be representative of the general schizophrenia patient and their caregivers. Another limitation is that although KAST is a good psychometric questionnaire, not all reliability and validity testing methods can be used. Compton et al[10] also pointed out that the lack of a gold standard for measuring knowledge about schizophrenia makes it difficult to assess the standard validity of KAST.