EQ-5D-Y Population Norms for Japanese Children and Adolescents

Objective This study was aimed at establishing population norms of EQ-5D-Y in Japan by a nationwide large sample survey. Methods We performed a door-to-door survey by visiting the homes of children/adolescents aged 8-15 years selected by random sampling. The planned sample size was 3600 from 100 districts in Japan. Children/adolescents were asked to respond to the EQ-5D-Y instrument, and their parents, to background questions on themselves and their children. Summary statistics by age/sex were calculated to obtain the Japanese population norms. A multiple linear regression model was used to examine the relationships between the EQ-5D-Y index and their parents' demographic factors, the children/adolescents' diseases/symptoms and the family environment. Results We collected 3636 responses from 100 districts. The overall EQ-5D-Y index values (all sexes, ages) ranged from 0.90 to 0.95. The percentage of respondents reporting full health ranged from 40 to 60%. In regard to the influence of the children/adolescents' diseases/symptoms on disutility, developmental disability showed the largest disutility values of 0.090. Sleeplessness and body pain were the symptoms that exerted the greatest influence on the EQ-5D-Y index; the effect sizes ranged from - 0.030 to - 0.098 for sleeplessness, and from - 0.023 to - 0.079 for body pain. The EQ-5D-Y index of children/adolescents with parents who reported severe stress was lower by 0.072 (p < 0.001), as compared with that of children/adolescents with parents reporting no stress. Conclusions Population norms of EQ-5D-Y were established for the first time. We also clarified the relationship between the EQ-5D-Y index value and the children/adolescents' diseases/symptoms and the family environment.