Validation of the Japanese version of the paediatric quality of life inventory rheumatology module

To translate and culturally adapt the Japanese version of the Paediatric Quality of Life Questionnaire (PedsQL) 3.0 Rheumatology Module (PedsQL-RM3.0JA) for children with paediatric rheumatic diseases, as well as to evaluate its reliability and validity.

This study included 76 patients aged 2-18 years and their parents, who completed the Japanese PedsQL 4.0 Generic Core Scale (PedsQL-GCS4.0JA) and PedsQL-RM3.0JA. Internal consistency (Cronbach's α), intraclass correlation coefficients, and validity were analysed using SPSS 29.

Child self-reports and parent proxy reports had Cronbach's α coefficients ranging from 0.781 to 0.938 and 0.722 to 0.915, respectively, indicating good to excellent reliability. Intraclass correlation coefficients exceeded 0.7 for most subscales. Physical Functioning and Emotional Functioning had moderate to strong correlations with the Pain and Daily Living subscales (r = 0.442-0.749), confirming concurrent and convergent validity. The sample size of infants (2-4 years) was insufficient for evaluation. The evaluation showed limited reliability in young children (5-7 years) due to a small sample size and developmental considerations.

The PedsQL-RM3.0JA demonstrated high reliability and validity in children aged 8 years and older, supporting its utility for evaluating health-related quality of life in paediatric rheumatic diseases in Japan.