Validation of the Chinese version of the Summated Xerostomia Inventory (SXI)

Abstract

The aim of this study was to validate the Chinese version of the Summated Xerostomia Inventory (SXI). The English SXI was translated into Chinese, cross-cultural adaptation and pilot tested. The final Chinese version of SXI was tested in a consecutive sample of 212 patients with xerostomia. The reliability of the Chinese version of SXI was determined through internal consistency and test-retest methods. The construct validity of SXI was analysed by content validity, construct validity, and convergent validity. Cronbach's alpha value for the SXI score was 0.798, and the test-retest intraclass correlation coefficient value for the SXI score was 0.837. Construct validity was proved by the presence of one-factor structure that accounted for 57.68% of the variance and fitted well into the model. The correlation between the total score of the SXI and the global oral health question was 0.75, indicating very good correlation (P<0.01). This study provided preliminary evidence concerning validity and reliability of the Chinese version of the SXI. The results provide initial evidence that the SXI may be a useful tool for the mainland Chinese xerostomia patients for both clinical and epidemiologic researches.