Validity of the health-related quality of life assessment in the ADORE study: Parent report form of the CHIP-child edition

Objectives: To examine the cross-sectional reliability and validity of the Parent Report Form of the Child Health and Illness Profile-Child Edition (CHIP-CE), a generic measure of health-related quality of life (HRQoL), in children with ADHD in the pan-European ADHD Observational Research in Europe (ADORE) study. Methods: Parents of children with ADHD (aged 6-18 years) in 10 European countries completed the CHIP-CE at the baseline visit (n=1,477; data missing for one patient). Analyses included determination of internal consistency reliability, ceiling and floor effects, factor analysis, and Pearson's correlations between CHIP-CE and other scales used to measure ADHD severity, problems and family strain. Results: Internal consistency reliability was good-to-excellent (Chronbach's α>0.70) for all CHIP-CE domains and subdomains, and almost no ceiling and floor effects were observed. Factor analysis of the subdomains yielded a 12-factor solution. The domainlevel factor analysis identified six factors, the four domains of Satisfaction, Comfort, Resilience and Risk Avoidance. The two subdomains of Achievement domain, Peer Relations and Academic Performance, were separate factors in this sample. There were moderate-to-high correlations between the CHIP-CE scales and measures of ADHD and family factors. The HRQoL of children in ADORE was dramatically lower than that of community youth,with mean CHIP-CE scores almost 2 standard deviations below community norms. Conclusions: The validity and reliability of CHIP-CE to measure HRQoL in children with ADHD across Europe was confirmed.