Quality-of-life: a many-splendored thing? Belgian population norms and 34 potential determinants explored by beta regression

PURPOSE: To identify determinants of health-related quality-of-life in the Belgian population and to provide age-specific population norms of health-related quality-of-life. METHODS: Between September 2010 and February 2011, a representative sample of 1774 persons (age 0–99) was surveyed using the standard Euroqol questionnaire (EQ-5D-3L) with a Visual Analogue Scale (VAS). Significant determinants were identified using multivariate beta (VAS) and one-inflated beta (EQ-5D) regression, the latter modelling the probability to be in perfect health separately from the average EQ-5D score if not in perfect health. RESULTS: Health-related quality-of-life depends largely on age and experience with severe disease. The probability to be in perfect health is highest for children. For 0–2 years children who are not in perfect health, proxies report EQ-5D and VAS scores as low as that of the elderly. Also smoking behaviour, educational attainment, pet ownership, working or having worked in health care, and potentially household size and 60+ living on their own (yes/no) are associated with health-related quality-of-life, whereas no association was found with gender, living in a single-parent home, educational attainment of mothers, alcohol consumption of 60+, having (grand-) children and the frequency of seeing them. The same determinants are significant for VAS and the probability to be in perfect health, but not for the average EQ-5D score if not in perfect health. CONCLUSIONS: The population norms provided can be used directly as input in health economic evaluations. Estimating health-related quality-of-life in children and developing statistical tools capturing the particular features of health-related quality-of-life measures are important areas for future research. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11136-017-1556-y) contains supplementary material, which is available to authorized users.