Measuring health status in early juvenile idiopathic arthritis: determinants and responsiveness of the child health questionnaire

OBJECTIVE: To assess the determinants and responsiveness of the Norwegian version of the Child Health Questionnaire (CHQ) in patients with early juvenile idiopathic arthritis (JIA) and to compare health status in patients and controls. METHODS: A total of 116 children (median age 8.4 yrs) with JIA and < 2.5 years of disease duration (median 11.0 mo) were examined by a pediatric rheumatologist and reassessed after a median of 10.0 months. Physical and psychosocial health were assessed by means of the CHQ, which provides summary scores for physical and psychosocial health, the Childhood Health Assessment Questionnaire (CHAQ), and the Child Behavior Checklist (CBCL, n = 32). Matched controls (n = 116), randomly selected from the general population, completed the CHQ at baseline. RESULTS: The patients with JIA had poorer physical health and slightly impaired psychosocial health compared with the controls 41.2 +/- 13.6 vs 55.2 +/- 7.3 (p < 0.001) and 51.0 +/- 7.5 vs 54.1 +/- 5.7 (p = 0.002), respectively]. The most important determinants of the CHQ physical summary score were the child's pain, morning stiffness, the CHAQ disability index, erythrocyte sedimentation rate (ESR), overall well-being, and physician's global assessment of disease activity. The psychosocial summary score correlated with the CBCL level of internalizing, externalizing, and total behavior problems. The standardized response mean for the physical summary score was large (0.96) for those who improved, and moderate (-0.60) for those who became worse. CONCLUSION: The CHQ discriminated between patients with early JIA and controls. The most important determinants of the CHQ physical summary score were the child's pain, morning stiffness, CHAQ, ESR, overall well-being, and physician's global assessment of disease activity. The CHQ was sensitive to clinical changes in children with JIA.