Generation, Selection, and Face Validation of Items for a New Generic Measure of Quality of Life: The EQ-HWB

•Currently, few generic measures for economic evaluation exist. This study describes the process of the item generation and face validation stages from the estimate quality-adjusted life-year project.•The face validation stage was conducted in 6 countries. Generally, participants favored brief items. Nevertheless, for some items, having examples and more information on the contexts could be helpful.•This was an initial validation test of items that should be used in the EQ Health and Wellbeing measure for economic evaluation of health and social care interventions.