Comparative Psychometric Performance of Common Generic Paediatric Health-Related Quality of Life Instrument Descriptive Systems: Results from the Australian Paediatric Multi-Instrument Comparison Study

Objective The aim of this study was to compare the psychometric performance of common generic paediatric health-related quality-of-life instrument descriptive systems (PedsQL generic core 4.0, EQ-5D-Y-3L, EQ-5D-Y-5L, Child Health Utility 9D [CHU9D], Assessment of Quality of Life 6D [AQoL-6D], and Health Utilities Index Mark 3 [HUI3]) by child age, report type, and health status. Methods Data for children aged 5–18 years were from the Australian Paediatric Multi-Instrument Comparison study. Ceiling effects, test–retest reliability, known-group validity, convergent and divergent validity, and responsiveness were assessed in the total sample and by child age (5–12 years vs 13–18 years), report type (self- vs proxy report), and health status. Instruments were scored using an exploratory level sum score (LSS) approach. Results Survey data were available for 5945 children, with follow-up data available for 2346 children. The EQ-5D-Y-3L demonstrated ceiling effects. The PedsQL, EQ-5D-Y-3L, EQ-5D-Y-5L, and CHU9D demonstrated acceptable test–retest reliability. All instruments demonstrated known-group, convergent, and divergent validity. The EQ-5D-Y-3L, EQ-5D-Y-5L, and CHU9D demonstrated responsiveness to improvements in health and the PedsQL, EQ-5D-Y-3L, EQ-5D-Y-5L, and CHU9D to worsening health. The AQoL-6D and HUI3 had inconclusive test–retest reliability and responsiveness evidence due to small sample size. Importantly, ceiling effects, test–retest reliability and responsiveness varied by subgroup. Conclusion Results reflect instrument performance using LSSs, which may differ to utility scores. In the total sample, the EQ-5D-Y-5L and CHU9D descriptive systems demonstrated evidence of good performance (i.e., meeting prespecified criteria) across all psychometric attributes tested. Performance varied by child age and report type, indicating room for considerations by population and study.