A Portuguese value set for the SF-6D.

Area of Science:

• Health Economics
• Psychometrics
• Public Health

Background:

• The SF-6D is a vital tool for cost-effectiveness analysis, providing quality-adjusted life-year (QALY) values.
• Estimating country-specific SF-6D weights is essential for accurate health economic evaluations.
• Portugal lacked specific SF-6D system weights, necessitating this study.

Purpose of the Study:

• To derive SF-6D preference-based utility weights for the Portuguese population.
• To compare the estimated Portuguese SF-6D weights with existing UK system weights.
• To facilitate cost-effectiveness analyses in Portugal using the SF-6D.

Main Methods:

• Valued 55 SF-6D health states using the Standard Gamble (SG) method with a representative Portuguese sample (n=140).
• Estimated multiple regression models (Random Effects, GLS, GEE) at individual and aggregate levels.
• Considered various functional forms to address skewed health-state valuation distributions.

Main Results:

• Developed robust SF-6D utility weights for Portugal, showing consistency with UK system weights.
• Identified potential under-prediction in models for states representing poor health.
• Models demonstrated significant coefficients and good overall fit, despite some estimation challenges.

Conclusions:

• The study provides essential preference-based quality of life weights for the Portuguese population, derived from SF-36 data.
• Findings support the use of these weights in health economic evaluations in Portugal.
• Caution is advised due to the small sample size, despite individual-level estimations.