Cross-cultural adaptation of a health status classification system in children with cancer. First results of the French adaptation of the Health Utilities Index Marks 2 and 3

Our objective was to adapt and validate the Health Utilities Index Mark 2 (HUI 2) and HUI 3 health status classification systems self-report questionnaire in a population of children with cancer, a group of 42 children already included in a multi-centre database designed by the Group on Brain Tumors in Children of the French Society for Pediatric Oncology. Children were recruited during a routine consultation. Most of them had completed treatment. The version of the questionnaire for French adults was adapted linguistically for children. Open-ended queries by children about the comprehensiveness of the questions and very low non-response rates showed a good acceptability of the questionnaire. The main psychometric properties of the HUI 2 and HUI 3 classification systems were assessed in 3 groups of raters (child, parent, physician): construct validity was tested against the rating of the child's health state on a Likert scale and through comparison with clinical data, and internal consistency was determined through multi-trait analysis. Weighted and unweighted kappa values were used to measure the inter-rater agreement between the child's, parent's and physician's assessment of the child's health state. The convergent validity was satisfactory, with better results when the physician's assessment was used. The most affected attributes were the expected ones (i.e., cognition, pain and emotion). Disagreement was observed between the 3 raters, more often in the same direction: taking the child's assessment as the reference, the parents tended to under-estimate the health status while physicians tended to over-estimate it.