Assessment of health-related quality of life in Taiwan (I): Development and psychometric testing of SF-36 Taiwan version

Objectives: This paper aims to document the development of the SF-36 Taiwan version for assessment of health related quality of life and perform psychometric testing of the scales. Methods: The study sample was composed of 18,142 subjects aged 12 and above from the 2001 Health Interview Survey. The psychometric testing, which included tests of data quality, scaling assumptions and reliability, was performed on a valid sample of 17,515 subjects. Results: Regarding data quality, the average scale missing rate of all items was less than 4% with male respondents tending to have higher missing rate than female ones, this trend held true for elderly respondents relative to the younger counterparts. In terms of tests of scale assumptions, item-scale correlation coefficients range from 0.40 to 0.83. Except for MH, the rest of the scales have passed the tests of item discriminant validity. Also, internal reliability has reached acceptable level for all scales (α>0.70), except for SF. Conclusions: In Summary, the SF-36 Taiwan version was shown to possess good psychometric properties. In order to enhance the explanatory power of SF-36 Taiwan version, further research is required to establish the norm and validate the instrument.