Transforming Latent Utilities to Health Utilities: East Does Not Meet West

Discrete choice experiments (DCEs) are a promising alternative to more resource-intensive preference elicitation methods such as time trade-off (TTO), as pairwise comparisons are more amenable to online completion, which can save time and money. However, modeling DCE data produces latent utilities which are on an unknown scale. Therefore, latent utilities need to be transformed to a full health-dead scale before they can be used in quality-adjusted life year calculations. We aimed to explore transformation functions from DCE-derived latent utilities to TTO-derived health utilities. We used EQ-5D-5L valuation data from eight different countries that collected both DCE and TTO data by using a standardized protocol. Results found less variation in the function that transformed latent utilities to health utilities in the western countries than in the eastern countries. While a global transformation function is not recommended, results suggest that regional transformation functions could potentially be used to derive health utilities from DCE data. Copyright © 2016 John Wiley & Sons, Ltd.