Development of a Spanish (Castillian) version of the Childhood Health Assessment Questionnaire. Measurement of health status in children with juvenile chronic arthritis.

OBJECTIVE To demonstrate that the Spanish (Castillian) version of the Childhood Health Assessment Questionnaire (cHAQ-S) is a valid and reliable instrument for measuring the health status of children with juvenile chronic (or rheumatoid) arthritis (JCA) and is sensitive to change. METHODS A conceptual translation of the original questionnaire into Spanish and two back-translations were performed. The cHAQ-S was completed by the parents of young children (aged 1 to 19 years) affected by JCA, and additionally by those children aged over 9. A second cHAQ-S was administered at least 15 months after the first one. RESULTS The cHAQ-S was administered to 79 patients of patients affected by JCA. The test-retest reliability was evaluated among 16 patients, and no significant differences between the first and second administration were found (0.88 versus 0.84; p > 0.6; intraclass correlation coefficient R = 0.94). The Cronbach's alpha coefficient was 0.948, indicating an excellent internal reliability with a mean correlation between the different components of the questionnaire varying from 0.3557 to 0.7831. For the between-observer reliability, an intraclass correlation coefficient of 0.96 was obtained. Correlations between DI (Disability Index) and several measures of disease activity were all statistically significant (Spearman's R ranged from 0.42 to 0.87; p < 0.005). Patients who improved showed similar improvement in the DI (p = 0.015), while patients who worsened showed a worsening of the DI (p = 0.1) and patients whose condition was stable showed no change in DI (p = 0.6). CONCLUSION The cHAQ-S is a feasible, reliable and valid instrument for the determination of the health status of Spanish children suffering from JCA. It is also sensitive to changes in the child's health status.