Child–Parent Agreement in the Assessment of Health-Related Quality of Life Using the CHU9D and the PedsQL(TM)

OBJECTIVE: This study examined the inter-rater agreement between child-self and parental proxy health-related quality of life (HRQoL) ratings (overall and domain level) using two different generic child-specific measures, the Child Health Utility 9D (CHU9D) and the Pediatric Quality of Life Inventory (PedsQL(TM)), in a community-based sample of Australian children. A secondary objective was to investigate the impact of age on child–parent agreement across the dimensions of the two measures. METHODS: A total of 85 child–parent dyads (children aged 6–12 years) recruited from the community completed the self and proxy versions of the CHU9D and the PedsQL(TM), respectively. The inter-rater agreement was estimated using Concordance Correlation Coefficients (CCC) and Gwet’s Agreement Coefficient (AC(1)) for the overall sample and across age-groups. RESULTS: Agreement was low for overall HRQoL for both the CHU9D (CCC = 0.28) and the PedsQL(TM) (CCC = 0.39). Across the CHU9D dimensions, agreement was the highest for ‘sad’ (AC(1) = 0.83) and lowest for ‘tired’ (AC(1) = 0.31). The PedsQL(TM) demonstrated stronger agreement (AC(1) = 0.41–0.6) for the physical health dimension but weaker for the psychosocial dimensions (AC(1) < 0.4). Except for the ‘tired’ dimension, agreement was consistent across age-groups with the CHU9D, whilst the PedsQL(TM) showed poor agreement for most of the psychosocial health items among the older age-groups only (8–10 and 11–12 years). CONCLUSION: This study highlights that the agreement between child and parent proxy reported HRQoL may be influenced by both the measure used and the age of the child. These findings may have implications for the economic evaluation of healthcare interventions and services in child populations when both child and proxy perspectives are considered in the assessment of child HRQoL.