Abstract: EQ-5D is used in cost-effectiveness studies underlying many important health policy decisions. It comprises a survey instrument describing health states across five domains, and a system of utility values for each state. The original 3-level version of EQ-5D is being replaced with a more sensitive 5-level version but the consequences of this change are uncertain. We develop a multi-equation ordinal response model incorporating a copula specification with normal mixture marginals to analyse joint responses to EQ-5D-3L and EQ-5D-5L in two different surveys, and use it to generate mappings between the alternative descriptive systems. We revisit a number of cost-effectiveness studies, mapping the original EQ-5D-3L measure onto a 5L valuation basis. We find that improvements in quality of life are valued less using EQ-5D-5L than using EQ-5D-3L but technologies with significant mortality gains may exhibit increased incremental quality-adjusted life-years. In conclusion, EQ-5D-3L and EQ-5D-5L can produce substantially different estimates of cost effectiveness and there is no simple proportional adjustment that can be made to reconcile these differences.
Speaker’s Bio: Dr Mónica Hernández, is a Reader in Health Econometrics in the School of Health and Related Research, University of Sheffield. Mónica has significant expertise in general statistical/econometrics modelling and methods development. Her current program of research focuses on the applied areas of mapping, the use of observational data, and more general microeconomic applications such as health concordance in couples, child development, obesity and the costs to the individual of disability and welfare programs. She is a current holder of an ESRC funded Biomarker Data Project Fellowship. She is also a member of the NICE DSU and the ISPOR Statistical Methods in Health Economics and Outcomes Research Special Interest Group. Mónica was a member of a Task Force to produce an international Good Practice Guide on mapping and provides training to industry and academics both through NICE and ISPOR.