An Investigation of Inter-Rater and Intra-Proxy Agreement in Measuring Quality of Life of Children in the Community Using the EQ-5D-Y-3L

Abstract

Background Self-reporting of health-related quality of life (HRQoL) in children is not always feasible. To date, proxy perspectives (Proxy versions 1 and 2) using the EQ-5D-Y-3L have not been explored for its impact on agreement with child self-report. Proxy version 1 requires the proxy to consider their own view of the child’s HRQoL (proxy-proxy), while with Proxy version 2, the proxy is asked to respond as they believe their child would self-report their HRQoL (proxy-child). This study compared the inter-rater and intra-proxy agreement (overall and dimension level) using the EQ-5D-Y-3L self, proxy-proxy, and proxy-child reports. Methods A community-based sample of child (aged 6–12 years) and parent dyads were invited to participate in a semi-structured interview. The child self-completed the EQ-5D-Y-3L independently of the parent who completed the EQ-5D-Y-3L from proxy-proxy and proxy-child perspectives. Agreement was determined using Concordance Correlation Coefficients (CCCs) for the overall (preference-weighted) HRQoL, while agreement at the dimension level was evaluated using Gwet’s agreement coefficient (AC 1 ). To assess the differences between the self and the two proxy reports, the Wilcoxon matched-pair signed-rank test was used. Results This study involved 85 child-parent dyads. The agreement between self and proxy overall HRQoL was low (fair) with both proxy-proxy (CCC = 0.28) and proxy-child (CCC = 0.26) reports. The largest discrepancy in the child-proxy agreement at dimension level with both the proxy versions was observed for ‘feeling worried, sad or unhappy’. Within this dimension, the proxy-child perspective resulted in a stronger agreement (AC 1 = 0.7, good) with child self-report compared with the traditional proxy-proxy perspective (AC 1 = 0.58, moderate). Although the preference-weighted HRQoL was consistent across both the proxy perspectives, a significant difference was observed in the EQ VAS scores ( p = 0.02). Conclusions This study demonstrates that choice of proxy perspective may have an impact on the problems reported on HRQoL dimensions and EQ VAS scores. However, in this community-based sample of generally healthy children, no significant difference was observed in the inter-rater agreement for child-self and proxy preference-weighted EQ-5D-Y-3L values based on proxy perspectives. While this suggests that preference-weighted data are not sensitive to the choice of perspective, these findings may differ for different HRQoL instruments and for alternative value sets with different properties. Supplementary Information The online version contains supplementary material available at 10.1007/s40273-024-01356-0.

Meeting the Challenges of Preference-Weighted Health-Related Quality-of-Life Measurement in Children

“…Examining optimal strategies for assessing preference-weighted HRQoL in young children inevitably requires close examination of alternative approaches to proxy assessment. Using the EQ-5D-Y-3L administered to a community sample of parent-child dyads, Khanna et al compared the reports of proxies asked to consider their own view of their child’s HRQoL to a proxy that responded as they believed their child would and to the child’s self-report [ 20 ]. Agreement between self and both proxy types was low, with the greatest disagreement observed for “feeling worried, sad or unhappy,” though agreement was better for proxies asked to report as they thought their child would.…”

“…The studies by Khanna et al and Bailey et al provide further insight into another fundamental aspect of measuring child health, namely the involvement of parents and caregivers, either as proxy reporters of their child’s health [ 20 ] or as individuals whose own health may be affected by their child’s condition [ 21 ]. A proxy perspective on a child’s health state whether “within the skin” or a parent rating, is often necessary, even in older children, if the child is too ill or otherwise unable to respond.…”