Valuing SF-6Dv2 Using a Discrete Choice Experiment in a General Population in Quebec, Canada

Area of Science:

• Health Economics
• Psychometrics
• Outcome Measurement

Background:

• An updated Short-Form 6-Dimension (SF-6D) Classification System (SF-6Dv2) necessitates new utility value sets.
• Previous versions of SF-6D value sets require updates to reflect the revised classification system.
• Accurate health utility values are crucial for cost-effectiveness analyses in healthcare.

Purpose of the Study:

• To estimate a new utility value set for the SF-6Dv2 classification system.
• To derive these values from a general population sample in Quebec, Canada.
• To ensure the new value set is consistent and reflects current population preferences.

Main Methods:

• A discrete choice experiment with time trade-off (DCE_TTO) was employed.
• Two designs were utilized: binary choice sets (Design 1) and best-worst choice sets including an "immediate death" scenario (Design 2).
• Logit models, including mixed logit for heterogeneity, were used to estimate the value set.

Main Results:

• 1153 participants completed the survey, with a combined model (Design 1 & 2) showing the best fit.
• The final SF-6Dv2 value set ranged from -0.683 to 1, with 13.01% negative values.
• Pain and vitality dimensions most significantly influenced preferences, with heterogeneity observed at severe health state levels.

Conclusions:

• A new SF-6Dv2 utility value set was successfully estimated for the Quebec, Canada population.
• The recommended value set is derived from an anchored consistent model combining both DCE designs.
• This value set is suitable for use in health economic evaluations within Quebec.