Description and valuation of health-related quality of life among the general public in Japan by the EuroQol

Objective. Health-related quality of life plays an important role in assessing the effectiveness of health care. The EuroQol is a generic instrument for describing and valuing health-related quality of life. To elicit health state descriptions and their preferences among the general public in Japan and compare them with cross-national data, a feasibility study for applying the EuroQol to the general public in Japan was carried out.
Subjects and methods. The subjects were 120 people aged 40s-60s randomly selected in a suburban area at Aichi Prefecture in Japan. In assessing health states and their preferences, the EuroQol valuation instrument (version 12, 1991) translated into Japanese was used. The questionnaires were distributed and collected by public health nurses. The valid responses (rate) were 89 (74%).
Results. The mean scores (raw scores) using the visual analogue scale (VAS) for one’s own health was 89.2. No statistically significant difference in VAS scores was observed for both sex and age. The contribution ratio of own health status, sex and age was 0.326 (p<0.0001). The main independent variables were three dimensions of health status.Valuations for core health states varied from 96.3 (no problems in each health status) to 6.8 (dead). These VAS scores in Japan were correlated with those from other countries (p<0.001). A multivariate analysis indicated that bias from own health status on preference valuations for core health states was not observed.
Conclusion. The health states and their preferences among the general public in Japan were estimated by using the EuroQol. The results show the feasibility of evaluation for health states quantitatively. Moreover, this study suggested cross-national and cross-cultural applicability of the EuroQol.