Reliability and Validity of the Turkish Version of SF-12 Health Survey

Objective: The aim of this study is to determine the psychometric properties of the Turkish version of the SF-12 Health - a widely used scale that assesses health - related quality of life - and to assess whether its psychometric properties are as good as with the 36 items long version (SF-36). Method: The study included a total of 190 participants including 138 young adults aged from 18 to 29 years (22.04 +/- 2.35) and 52 older adults aged from 60 to 80 years (67.27 +/- 5.22). The relationships between EQ-5D-3L, CES-D and SF-12 scales were investigated for content, convergent and divergent, criterion-related and the known-groups construct validity. In order to assess reliability, internal consistency and item-total correlation coefficients were calculated and test re-test analyses were conducted. Results: The internal consistency coefficients of the scale were found to be satisfactory (for the components alpha=0.73 and 0.72). Consistent with the original study, physical and mental components of the SF-12-TR were found to be strongly correlated with the components of the SF-36 and explained, respectively, 86.6% and 92.4% of the variance. The components of the SF-12-TR were found to be moderately or strongly correlated to the sub-dimensions of the EQ-5D-3L and CES-D, which measure the same structures, while they were unrelated or weakly correlated with the subdimensions measuring different structures. Conclusion: The findings indicated that the psychometric properties of the Turkish form of SF-12-TR are similar to the original version, and the SF-12-TR can be used as an alternative to the SF-36-TR in clinical and research settings in our country.