A Time Trade-off-derived Value Set of the EQ-5D-5L for Canada.
BACKGROUND
The 5-level version of the EQ-5D (EQ-5D-5L) was recently developed. A number of preference-based scoring systems are being developed for several countries around the world.


OBJECTIVE
To develop a value set for the EQ-5D-5L based on societal preferences in Canada.


METHODS
We used age, sex, and education quota sampling from the general population from 4 cities across Canada. Composite time trade-off (cTTO) and traditional time trade-off (tTTO) were used as the main elicitation technique. A total of 86 EQ-5D-5L health states grouped into 10 blocks were valued using cTTO, whereas a subset of 18 severe states was also valued using tTTO. Participants meeting predefined inconsistency criteria were excluded from the analyses. For the value set development, we used tTTO and positive cTTO values, while censoring negative and zero cTTO values at zero. Models with the main effects presented using linear terms combined with various additional terms were estimated. The preferred model was selected based primarily on logically ordered coefficients, and secondly model fit.


RESULTS
Of the 1209 participants who completed the interview, 136 met criteria that excluded them from the primary analyses. The demographics and socioeconomic status of the remaining 1073 participants were similar to the Canadian general population. The preferred model has 5 linear terms for the main effects, a term for level 4 or 5 for each dimension, and a term for the squared total number of level 4 or 5 beyond the first. For this preferred model, the health utilities ranged from -0.148 for the worst (55555) to 0.949 for the best (11111) EQ-5D-5L states.


CONCLUSIONS
This is the first TTO-based value set of the EQ-5D-5L for Canada. It can be used to support the health utility estimation in economic evaluations for reimbursement decision making in Canada.
*Department of Clinical Epidemiology and Biostatistics, McMaster University†Program for Health Economics and Outcome Measures (PHENOM)‡Father Sean O'Sullivan Research Centre, St. Joseph's Healthcare, Hamilton§Child Health Evaluative Sciences Group, Hospital for Sick Kids, Toronto, ON∥School of Population and Public Health, University of British Columbia, Vancouver, BC¶School of Public Health, University of Alberta, Edmonton, AB#School of Medicine, Université de Montréal, Montreal, QC, Canada.
Feng
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Xie
Eleanor
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Pullenayegum
Kathy
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Gaebel
Nick
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Bansback
Stirling
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Bryan
Arto
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Ohinmaa
Lise
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Poissant
Jeffrey A
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Johnson
D002170:Canada; D005260:Female; D006304:Health Status; D006801:Humans; D016014:Linear Models; D008297:Male; D015233:Models, Statistical; D011594:Psychometrics / Q000295:instrumentation; D011788:Quality of Life / Q000523:psychology*; D011795:Surveys and Questionnaires / Q000592:standards*