Updated version of Japanese Childhood Health Assessment Questionnaire (CHAQ).

Objectives: The Childhood Health Assessment Questionnaire (CHAQ) is one of the most widely used self- report questionnaires to measure functional status in Juvenile idiopathic arthritis (JIA). The Japanese version of the CHAQ (JCHAQ) has been revised to meet requirements of clinical international trials which need the same number of questions in each functional area of the CHAQ.Methods: The original JCHAQ consisted of 36 items, measuring eight functional areas. This was changed to 30 items of questionnaire so that each functional area has same number of questions as the original US English version. The revised version was professionally translated from English to Japanese, reviewed, and validated with Japanese JIA patients.Results: A total of 42 JIA patients were enrolled in the validation: seven systemic, 30 polyarticular/oligoarticular and five enthesis related. Most patients were well controlled and the median disability index (DI) scores was 0.0 [0-0.03]; however, significant correlation was seen with visual analog scale (VAS) of pain, VAS overall well-being, physician VAS, DAS (Disease Activity Score) 28-ESR, and JADAS (Juvenile Arthritis Disease Activity Score)-27. In comparison of two groups of disease activity, remission or inactive/low disease activity vs. moderate/high disease activity, both DAS28-ESR and JADAS-27 showed significant correlation with DI.Conclusion: The updated JCHAQ was a reliable and valid tool for the functional assessment of children with JIA. It is more suitable for international and transitional comparison.