In this blog we (1) summarise the current status of the EQ-5D-5L value set for England; (2) highlight NICE’s recent statement on the values to be used in the reference case; (3) briefly explain why there are differences between the EQ-5D-3L and EQ-5D-5L; and (4) discuss why those differences might be important. We then (5) explain the next steps, including an independent quality assurance of the value set, and (6) provide an overview of current research projects underway at OHE to provide further evidence on the implications of new value sets for HTA and other uses.
In this blog we (1) summarise the current status of the EQ-5D-5L value set for England; (2) highlight NICE’s recent statement on the values to be used in the reference case; (3) briefly explain why there are differences between the EQ-5D-3L and EQ-5D-5L; and (4) discuss why those differences might be important. We then (5) explain the next steps, including an independent quality assurance of the value set, and (6) provide an overview of current research projects underway at OHE to provide further evidence on the implications of new value sets for HTA and other uses.
1. What is the current status of the EQ-5D-5L value set for England?
An English value set for the EQ-5D-5L, the new five-level version of the EuroQol Group’s EQ-5D instrument, is now available. This is the output of a research collaboration led by Professor Nancy Devlin of OHE and Professor Ben van Hout of the University of Sheffield’s School of Health and Related Research.
The value set study is reported in two papers, both now available open-access in Health Economics. The first paper summarises the methods used to elicit stated preferences from the general public, reports the value set produced from that work and compares it to the original EQ-5D-3L value set for the UK and the ‘crosswalk’ algorithm used to provide an interim means of valuing EQ-5D-5L data. The second paper provides details of the innovative methods used to model the stated preference data to produce the EQ-5D-5L value set.
Earlier version of both papers were released as OHE Research Papers in 2016. The purpose of the Research Paper versions was to make the work-in-progress publicly accessible and to stimulate discussion and critical comment. The Health Economics papers contain some changes in comparison to the earlier versions – these are the result of feedback received as part of the journal’s peer review process. However, the practical impact of the changes is small and the overall conclusions of the research remain the same.
2. What is NICE’s current position on the EQ-5D-5L?
NICE recently released a position statement on the use of the EQ-5D-5L value set for England. Key elements are that:
- the EQ-5D-3L value set continues to be used for reference case analyses;
- where EQ-5D-5L data have been collected, reference case analyses should calculate utilities by mapping the EQ-5D-5L descriptive system data onto the EQ-5D-3L value set;
- the mapping function developed by van Hout et al. (2012) should be used for reference case analyses of EQ-5D-5L data;
- NICE supports sponsors of prospective clinical studies continuing to use the EQ-5D-5L to collect data on quality of life.
3. What are the differences between the EQ-5D-5L and the EQ-5D-3L, and why might that be important?
There are two differences between the two questionnaires:
a) The way health is described is different. The EQ-5D-5L has five levels rather than three, and has improved the labels used for certain levels. For example, for the worst level of mobility problems, ‘Confined to bed’ in the EQ-5D-3L has been replaced by ‘Unable to walk about’ in the EQ-5D-5L.
b) The way health states values are derived is different. Value sets for the EQ-5D-5L around the world, including the value set for England, have been produced using an international protocol developed by the EuroQol Group. The methods used to collect and model preference data are different from those that were used to generate the EQ-5D-3L value set. Differences in values might also be expected because the Measurement and Valuation of Health (MVH) study underpinning the EQ-5D-3L value set was conducted over two decades ago.
The overall difference between the EQ-5D-5L and the EQ-5D-3L will be a product of differences in both description and valuation.
OHE has previously reported on the important differences that exist between the UK EQ-5D-3L value set and the new EQ-5D-5L value set for England (Mulhern et al, 2017).
4. What will happen next?
NICE says that it intends to review its position in August 2018.
In line with the Macpherson report recommendations on quality assurance of modelling work affecting government policy, the English Department of Health will commission an independent quality assurance of the methods used to create the EQ-5D-5L value set for England.
Speaking on behalf of the value set for England study team, OHE’s Professor Devlin comments, “Given the importance of the EQ-5D-5L value set for health technology appraisal in England and elsewhere, we expected from the outset that the new EQ-5D-5L value set would be subject to close scrutiny. We have prepared our data and code for sharing to facilitate the independent quality assurance required by the government.”
Professor Devlin also adds, “Value set studies inevitably involve decisions about how to handle the data and what assumptions to use in modelling. Our project was overseen by a steering group comprising Department of Health senior economists, senior representatives from NICE and academic health economists. All aspects of the data and modelling were reported to the steering group members at regular meetings, and their guidance was sought on the modelling approaches we used.”
5. What further research is OHE doing?
A range of other research projects are also either planned or underway, both in the UK and internationally, commissioned by NICE, the EuroQol Group and other organisations, to better understand the differences between the EQ-5D-3L and the EQ-5D-5L.
These include the following studies underway at OHE:
- Comparing the EQ-5D-3L and EQ-5D-5L in a cohort of cancer patients – a collaboration between OHE, Curtin University and King’s College London.
- A study being led by OHE to re-model the original EQ-5D-3L UK valuation data using the innovative modelling methods used in the EQ-5D-5L value set study in England – preliminary results from that study will be presented at the EuroQol Scientific Plenary Meeting in September.
- Comparing the EQ-5D-3L and EQ-5D-5L in a cohort of diabetes patients, in collaboration with the Centre for Health Economics Research and Evaluation, University of Technology Sydney.
- Cost utility analyses using EQ-5D: does how the utility values are derived matter? A collaboration between OHE and the National University of Singapore.
The EuroQol Research Foundation has established a 3L/5L Taskforce (co-chaired by Professors John Brazier and Nancy Devlin) to coordinate a number of other research projects to better understand the differences between the EQ-5D-3L and EQ-5D-5L descriptive systems and values sets and the implications for users.
Both of the Health Economics papers are now available open access:
Devlin, N., Shah, K., Feng, Y., Mulhern, B. and van Hout, B., 2017. Valuing health-related quality of life: An EQ-5D-5L value set for England. Health Economics. DOI: 10.1002/hec.3564
Feng, Y., Devlin, N., Shah, K., Mulhern, B. and van Hout, B., 2017. New methods for modelling EQ-5D-5L value sets: An application to English data. Health Economics. DOI: 10.1002/hec.3560
For more information, please contact Nancy Devlin.
Syntax files available to download here.
The syntax is based on the value set reported in Appendix II of Devlin et al. (2017). The 5L indices calculated are identical to the results that use the central estimates reported in Table II.
