Subjective health values of individuals with diabetes in Japan: comparison of utility values with the SF-36 scores.

To investigate the characteristics of utility values for current health states and the Medical Outcome Study Short Form 36 (SF-36) scores in terms of patients' preferences, we performed the utility assessment using the visual analog scale (VAS) and the standard gamble (SG) techniques, and the SF-36 questionnaires on 68 hospitalized individuals with diabetes. Sixty patients responded appropriately. The SG value, 0.93 +/- 0.12 (mean +/- S.D.), was significantly higher than the VAS value, 0.65 +/- 0.21 (P<0.001). A tendency for the SF-36 subscale scores to decrease compared to national normative data for Japan was observed. Diabetic conditions such as glycated hemoglobin level and daily insulin injection were not significant predictors of either utility or SF-36 scores, while diabetic complications affected two subscales of the SF-36. The VAS values were somewhat related to the SF-36 subscale scores but the SG values had no relation to any SF-36 scores. These results suggest the difficulty of estimating the subjective health values of the patients only through the traditional clinical indicators and the SF-36 scores.