The PRET project: Preparation for the Re-valuation of the EQ-5D Tariff

Project overview

Resources are limited and need to be allocated efficiently. The National Institute for Health and Clinical Excellence (NICE) was set up to help make better health care resource allocation decisions. NICE bases its recommendations on cost effectiveness, and the EQ-5D is the preferred instrument to use when quantifying the health related quality of life impact of medical interventions. EQ-5D is a tool that classifies 243 different health states with 5 different dimensions of health (mobility, self care, usual activities, pain/discomfort, anxiety/depression), each with an identified level of severity.

NICE uses an EQ-5D "tariff". This is a set of numbers that indicate the level of health related quality of life of each EQ-5D health state, on a scale with 1 for full health and 0 for dead (range -0.594 to 1, where negative values are valued as worse than dead). By comparing the different EQ-5D health states patients are in before and after treatment, analysts can calculate how effective the treatment is.

The current EQ-5D tariff is based on a survey in 1994. The study asked members of the general public to "value" a selection of hypothetical EQ-5D states using a specifically designed questionnaire. However, in the past 15 years, there have been various developments that have lead to the need for a "re-evaluation" of the EQ-5D (in particular the development of a new version of the EQ-5D with 3,125 possible health states to generate a "tariff" value for). In order for NICE to make the most appropriate decisions, the EQ-5D population value set needs to be one that is up to date, based on the latest understanding of how to value health states.

The PRET project is a methodological piece of work that will contribute to the re-valuation of the EQ-5D tariff. The project will investigate methodological issues relating to the methods used to value health states using online surveys and face to face interviews. The first stage is a large scale online survey to gauge the relevant concerns, where a range of methodological issues can be explored by surveying a large number of people, but not in much detail. There is an extension to the first stage (called PRET-AS, for "Additional Sample", funded by the EuroQol group who developed the EQ-5D) which is a further online survey to look into two techniques for valuing health states in more detail.  The second and third stages are smaller scale interview studies, where researchers can ask participants more detailed questions. The final stage of the project tests out a range of methods for valuing health states using in depth interviews.

The PRET project commenced in September 2010, and the four stages described above were completed by March 2012. We have presented the work at international conferences, and descriptions of the methods and results of some components of the project are available online (see the reference list below for links). The final HTA report was published in 2014.

Research team

Nick Bansback (University of British Columbia), John Brazier (HEDS), Ken Buckingham, John Cairns (London School of Health and Tropical Medicine), Nancy Devlin (Office of Health Economics), Paul Dolan (London School of Economics), Arne Risa Hole (Department of Economics), Georgios Kavetsos (London School of Economics), Louise Longworth (Brunel University), Brendan Mulhern (HEDS), Donna Rowen (HEDS), Aki Tsuchiya (HEDS, and Department of Economics)

References

Peer reviewed publications

Mulhern B, Bansback N, Brazier J, Buckingham K, Cairns J, Devlin N, Dolan P, Hole AR, Kavetsos G, Longworth L, Rowen D, Tsuchiya A. (2014). Preparatory study for the re-valuation of the EQ-5D tariff: Methodology Report. Health Technology Assessment, 18(12).

Dolan P, Kavetsos G, Tsuchiya A. (2013). Sick but satisfied? The impact of health and life satisfaction on choice between health scenarios. Journal of Health Economics, 32(4):708-714.

Mulhern B, Longworth L, Brazier JE, Rowen D, Bansback N, Devlin N, Tsuchiya A. (2013). Health state valuation questions: Head to head comparison on online and CAPI. Value in Health, 16(1): 104-13.

Bansback N, Hole AR, Mulhern B, Tsuchiya A (2014), Testing a discrete choice experiment including duration to value health states for large descriptive systems: addressing design and sampling issues. Social Science and Medicine, 144: 38-48

Discussion papers available online

Mulhern B, Longworth L, Brazier J, Bansback N, Devlin N, Tsuchiya A. (2012). Health state valuation and mode of administration: Head to head comparison of online and CAPI. HEDS Discussion Paper, 12/08. (available here; PDF, 313KB)

Tsuchiya A, Mulhern B. (2011). Preparation for the Re-valuation of the EQ-5D Tariff (PRET) project: Overview of methods for project stages 1-3. HEDS Discussion Paper, 11/16. (available here; PDF, 766kb) 

Conference papers and presentations (please contact Aki Tsuchiya for copies of this work)

Bansback N, Hole AR, Mulhern B, Tsuchiya A. (2013), Further exploration of Discrete Choice Experiments with a duration attribute to value health states, Health Economics Study Group, Warwick, Jun 2013, and the EuroQol Group Plenary, Montreal, Sep 2013.

Mulhern B. (2013). Using a Discrete Choice Experiment with duration to value health states: A feasibility study using EQ-5D-5L. International Health Economics Association, Sydney, Jul 2013.

Mulhern B, Tsuchiya A, Brazier J, Rowen D. (2012). How do respondents perceive health state valuation exercises? A ‘think aloud’ study investigating Time Trade Off and Discrete Choice Experiments. EuroQol group plenary, Rotterdam, Sept 2012.

Tsuchiya A, Bansback N, Hole AR, Mulhern B. (2012). Using a Discrete Choice Experiment with duration to value health states: A feasibility study using EQ-5D-5L. EuroQol Group Plenary, Rotterdam, Sept 2012.

Bansback N, Hole AR, Mulhern B, Tsuchiya A. (2012). Using a Discrete Choice Experiment with duration to value health states: A feasibility study using EQ-5D-5L. Health Economics Study Group, Oxford, Jun 2012 and EuroQol Group Plenary, Rotterdam, Sep 2012.

Mulhern B, Tsuchiya A, Devlin N, Buckingham K, Rowen D, Brazier J. (2012). A comparison of three binary choice methods for health state valuation. Health Economics Study Group, Aix-en-Provence, Jan 2012. (available here; PDF 927KB)

Mulhern B. (2011). Using a Discrete Choice Experiment incorporating duration to value health states (The PRET-AS Study). International Society for Pharmacoeconomics and Outcomes Research, Madrid, Nov 2011. (presented as part of a EuroQol group workshop, slides available here; PDF 163KB)

Mulhern B, Tsuchiya A, Rowen D, Devlin N, Bansback N, Longworth L, Brazier JE. (2011). Health state valuation questions: Head to head comparison on online and CAPI. EuroQol group Plenary, Oxford, Sept 2011.

Tsuchiya A, Mulhern B, Buckingham K, Devlin N. (2011) Testing Lead Time TTO issues in an online environment. EuroQol group Plenary, Oxford, Sept 2011.

Mulhern B, Tsuchiya A, Rowen D, Devlin N, Bansback N, Longworth L, Brazier JE (2011). Health state valuation questions: Does mode of administration matter? Health Economics Study Group, Bangor, June 2011.

Mulhern B, Tsuchiya A, Brazier J, Rowen D. (2012). How do respondents perceive health state valuation exercises? A ‘think aloud’ study investigating Time Trade Off and Discrete Choice Experiments. EuroQol group plenary, Rotterdam, Sept 2012.

Acknowledgements and disclaimer

PRET was funded by the MRC-NIHR Methodology Research Programme (MRC ref.G0901500). PRET-AS was funded by the EuroQol group as an extension to the PRET project, with formal agreement from the MRC. The EQ-5D and EQ-5D-5L are intellectual property of the EuroQol Group. John Brazier, Nancy Devlin, Louise Longworth, and Aki Tsuchiya are members of the EuroQol Group. PRET and PRET-AS were carried out independently of the funders.

Further information

For further information about the project please contact Aki Tsuchiya.