Estimating a WTP-based value of a QALY: the 'chained' approach

Area of Science:

• Health Economics
• Health Policy
• Public Health

Background:

• Valuing quality-adjusted life years (QALYs) is crucial for health economic evaluations and measuring healthcare effectiveness in Europe.
• Existing methods for eliciting the monetary value of a QALY face challenges, often resulting in excessively high estimates.
• The EuroVaQ project aimed to develop more robust methods for determining QALY value through public surveys.

Purpose of the Study:

• To develop and test an adapted 'chained' approach for eliciting the societal willingness-to-pay (WTP) for a QALY.
• To overcome documented issues with previous methods, particularly the tendency towards exceedingly high WTP per QALY values.
• To estimate the monetary value of a QALY based on a large-scale European public survey.

Main Methods:

• Utilized an adapted 'chained' approach involving eliciting utility values for health states (using standard gamble and time trade-off) and then monetary values to avoid health states.
• Conducted a large-scale internet-based survey across 9 European countries, achieving nearly 22,000 responses.
• Analyzed data using trimmed and untrimmed means, and medians to estimate the willingness-to-pay per QALY.

Main Results:

• The adapted 'chained' approach yielded QALY values generally on the lower side compared to some previous estimates.
• Trimmed mean willingness-to-pay per QALY estimates across all countries ranged from $18,247 to $34,097.
• Untrimmed means were higher, and medians were lower, indicating variability in responses.

Conclusions:

• The adapted 'chained' approach shows potential as a useful technique for estimating willingness-to-pay per QALY.
• The study highlights the need for further methodological refinement to address remaining challenges in QALY valuation.
• The findings contribute to ongoing efforts to establish sounder methods for health economic evaluations across Europe.