Loss aversion in EQ-5D-Y-3L: does it explain differences in willingness to trade-off life years in adults and children?

Earlier work has shown that adults valuing health for 10-year-old children (i.e., in a child perspective) are more reluctant to trade-off life duration than for themselves, generating higher utilities in composite time trade-off (cTTO). The main motivation of this study is to explore if this reluctance can be explained through loss aversion, i.e., losses of life duration weighing more than gains of the same size. 100 UK adults completed cTTO tasks for six EQ-5D-Y-3L states and tasks measuring loss aversion. Both sets of tasks were completed from the child perspective and for the respondent themselves, enabling perspective-dependent correction for loss aversion. A slight majority of participants was explicitly more loss averse for children than for themselves. Health state utilities were higher in the child perspective both before and after correction for loss aversion. Differences between utilities elicited in both perspectives and the variance of cTTO utilities increased considerably after correction. The results suggest that loss aversion does not explain differences in willingness to trade-off life duration between perspectives. Hence, it remains unclear if correction for loss aversion should be recommended when using EQ-5D-Y-3L utilities in practice.