New HEDS Discussion Paper - Estimating a preference-based index for mental health from the Recovering Quality of Life (ReQoL) measure : valuation of ReQoL-UI

Anju Devianee Keetharuth, Donna Rowen, Jakob Bue Björner and John Brazier

Dr Anju Devianee Keetharuth

Abstract

Objectives There are increasing concerns about the appropriateness of generic preference-based measures to capture health benefits in the area of mental health. This study estimates preference weights for a new measure, Recovering Quality of Life (ReQoL-10), to better capture the benefits of mental health care.

Methods Psychometric analyses of a larger sample of mental health service users (n = 4266) using confirmatory factor analyses and item response theory (IRT) were used to derive a health state classification system and inform the selection of health states for utility assessment. A valuation survey with members of the UK public representative in terms of age, gender and region was conducted using face-to-face interviewer administered time-trade-off (TTO) with props. A series of regression models were fitted to the data and the best performing model selected for the scoring algorithm.

Results The ReQoL-UI classification system comprises six mental health items and one physical health (PH) item. Sixty-four health states were valued by 305 participants. The preferred model was a random effects model, with significant and consistent coefficients and best model fit. Estimated utilities modelled for all health states ranged from -0.195 (state worse than dead) to 1 (best possible state).

Conclusions The development of the ReQoL-UI is based on a novel application of IRT methods for generating the classification system and selecting health states for valuation. Conventional TTO was used to elicit utility values that are modelled to enable the generation of QALYs for use in cost-utility analysis of mental health interventions.

Download the HEDS Discussion Paper here

HEDS PhD Opportunity - Valuing well-being alongside health: What can and should be done?

HEDS PhD Opportunity - Valuing well-being alongside health: What can and should be done?

Details

Health preferences inform resource allocation decisions around which treatments are recommended for use on the basis of their relative cost-effectiveness. Typically generic preference-based measures of health that can be used across all conditions are used to generate quality adjusted life years (QALYs) to inform cost-effectiveness analyses. The QALY combines both quantity and quality of life by assigning a value to quality of life on a 0 (for states as bad as being dead) to 1 (for full health) scale where values below 0 indicate that the state is worse than being dead. A generic preference-based measure of health consists of: 1) a classification system that is used to describe the health of a person and 2) a value set that generates a utility value that reflects how good or bad people think living in the health state would be. 

Recent research has focused on widening the classification system used to measure health to capture aspects beyond health to focus on domains such as quality of life. This presents challenges for the methods used to elicit utility values and the scope of the QALY itself and its role in informing cost-effectiveness analyses. Research challenges remain around the valuation of measures including: whose preferences to use (patients or general public); which elicitation technique to use; data collection mode; selection of states for valuation; how to aggregate and use these preferences to inform decisions around healthcare resource allocation. 

This PhD will contribute to methodological developments and understanding in the area of eliciting preferences for states that combine both health and wellbeing. The PhD will involve a literature review and primary research using a mixed methods approach involving both qualitative and quantitative research. The student will initially conduct a literature review of valuation methodology to inform the primary data collection. Qualitative work involving interviewers and/or focus groups will be undertaken to explore appropriate elicitation techniques and protocols, and whose preferences to use. Informed by the results of the qualitative work, a larger valuation survey will be conducted to further explore appropriate techniques and data collection mode. 

This project will be contributing methodological research to the Extending the QALY project, which is developing a broad measure of quality of life for use in economic evaluations across health and social care https://scharr.dept.shef.ac.uk/e-qaly/about-the-project/. The Extending the QALY project is funded by a Medical Research Council Industry Collaboration Award with the Euroqol Group. 

This PhD project aligns strongly with the Health Economics and Decision Science work theme of measuring and valuing health. The student will work closely with the ScHARR Outcomes group and benefit from engagement with current preference elicitation work. 

Funding Notes

The UPGRC Scholarships for Medicine, Dentistry & Health are 3.5 years in duration and cover fees and stipend at Home/EU level. Overseas students may apply but will need to fund the fee differential between Home and Overseas rate from another source. 

This project is also being advertised for the China Scholarship Council Award, further details can be found here: https://www.sheffield.ac.uk/postgraduate/phd/scholarships/csc 

The deadline for applications is 5pm on the 23rd January. 

Professor John Brazier

For further details you can send enquiries to  Professor John Brazier or  Dr Donna Rowan

Dr Donna Rowan