EQ-5D-5L: Smaller steps but a major step change?

Comparing the EQ-5D-5L crosswalks and value sets for England, the Netherlands and Spain: Exploring their impact on cost-utility results

This study compares the five-level EuroQol five-dimension questionnaire (EQ-5D-5L) crosswalks and the 5L value sets for England, the Netherlands, and Spain and explores the implication of using one or the other for the results of cost-utility analyses. Data from two randomized controlled trials in depression and diabetes were used. Utility value distributions were compared, and mean differences in utility values between the EQ-5D-5L crosswalk and the 5L value set were described by country. Quality-adjusted life years (QALYs) were calculated using the area-under-the-curve method. Incremental cost-effectiveness ratios (ICERs) were calculated, and uncertainty around ICERs was estimated using bootstrapping and graphically shown in cost-effectiveness acceptability curves. For all countries investigated, utility value distributions differed between the EQ-5D-5L crosswalk and 5L value set. In both case studies, mean utility values were lower for the EQ-5D-5L crosswalk compared with the 5L value set in England and Spain, but higher in the Netherlands. However, these differences in utility values did not translate into relevant differences across utility estimation methods in incremental QALYs and the interventions' probability of cost-effectiveness. Thus, our results suggest that EQ-5D-5L crosswalks and 5L value sets can be used interchangeably in patients affected by mild or moderate conditions. Further research is needed to establish whether these findings are generalizable to economic evaluations among severely ill patients.

Developing Accessible, Pictorial Versions of Health-Related Quality-of-Life Instruments Suitable for Economic Evaluation: A Report of Preliminary Studies Conducted in Canada and the United Kingdom

A key component of the current framework for economic evaluation is the measurement and valuation of health outcomes using generic preference-based health-related quality-of-life (HRQoL) instruments. In 2015, a research synthesis reported the absence of conceptual and empirical research regarding the appropriateness of current preference-based instruments for people with aphasia-a disorder affecting the use and understanding of language-and suggested the development and validation of an accessible, pictorial variant could be an appropriate direction for further research. This paper describes the respective rationale and development process for each of three preliminary studies that have been undertaken to develop pictorial variants of two widely used preference-based HRQoL instruments (EQ-5D-3L and EQ-5D-5L). The paper also proposes next steps for this program of research, drawing on the lessons learned from the preliminary work and the demand for a pictorial preference-based instrument in the research community. Guidance for the use of the preliminary, pictorial instruments is also provided.