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Published on: January 9, 2016
A shortcut to mean-based time tradeoff tariffs for the EQ-5D?
Kim Rand-Hendriksen1,2, Liv Ariane Augestad1, Fredrik A Dahl1
1Health Services Research Centre, Akershus University Hospital, Lørenskog, Norway (KRH, LAA, FAD, KS)
Summary
Simplified health state valuation using collapsed time tradeoff (cTTO) is effective. This abbreviated method accurately predicts full TTO tariff values, reducing costs and time in EQ-5D valuation studies.
Area of Science:
- Health Economics
- Psychometrics
- Outcome Measurement
Background:
- Time Tradeoff (TTO) is a standard but resource-intensive method for EQ-5D valuation.
- TTO involves categorizing health states as better than death (BTD), worse than death (WTD), or equal to death (ETD), and assessing unwillingness to trade (UTT) lifetime.
- The study investigates the informational value of conventional TTO tasks beyond initial categorization.
Purpose of the Study:
- To assess the value of information gained from continuing conventional TTO tasks.
- To determine if EQ-5D tariff values can be predicted using a simplified categorization method (BTD, WTD, ETD, UTT).
Main Methods:
- Utilized data from the UK EQ-5D valuation study (n=2997).
- Developed a collapsed TTO (cTTO) system assigning values: WTD=-.5, ETD=0, BTD=.5, UTT=1.
- Created a regression-based cTTO tariff and compared it to the full TTO (fTTO) tariff.
Main Results:
- WTD values did not correlate with health state severity.
- Mean fTTO and mean cTTO values showed a correlation greater than .999.
- fTTO tariff values strongly correlated with cTTO tariff values (r > .999).
Conclusions:
- Initial health state categorization (UTT, BTD, ETD, WTD) provides most of the information for tariff values.
- The WTD task lacks discriminatory power for health state severity.
- TTO valuation can be simplified using the cTTO method, offering significant efficiency gains.
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