Reliability and validity of the Japanese version of the KIDSCREEN-52 health-related quality of life questionnaire for children/adolescents and parents/proxies.

Objectives: The present study aimed to assess the reliability and validity of the Japanese version of KIDSCREEN-52 (J-KIDSCREEN-52), a generic questionnaire used to assess health-related quality of life (HRQOL) among children/adolescents and parents/proxies.

Methods: We conducted a school-based study, in which 1564 children and adolescents aged 8-18 years and their 1326 parents participated from five schools. They were asked to complete two questionnaires (the J-KIDSCREEN-52 and the Pediatric Quality of Life Inventory (PedsQL)), and the Oslo 3-Item Social Support (OSS-3) scale. Internal consistency reliability was measured using the Cronbach's alpha coefficient. Test-retest reliability was assessed by the Intraclass Correlation Coefficient (ICC) in the one-way random effects model in sub-samples taken approximately three to four weeks apart. Agreement between the ratings of the child and parent was evaluated using the ICC in the two-way mixed effects model among 681 pairs.

Results: For the overall sample, Cronbach's alpha values of 10 dimensions were ≥0.70, except for one dimension. Test-retest ICCs were ≥0.60 for nearly all dimensions. Correlation coefficients between the J-KIDSCREEN-52 and the PedsQL dimensions indicated a reasonable convergent validity. Parent ratings corresponded well with child ratings (ICC = 0.38-0.62). Statistically significant differences in mean T scores were dependent on gender for seven dimensions, age group for all dimensions, and health status for two dimensions.

Conclusions: The J-KIDSCREEN-52 questionnaires child/adolescent and parent/proxy versions demonstrated acceptable levels of reliability and validity.