ARE HEALTHY-YEARS EQUIVALENTS AN IMPROVEMENT OVER QUALITY-ADJUSTED LIFE YEARS

The construct of the healthy-years equivalent (HYE) has been proposed as an alternative to the quality-adjusted life year (QALY) on the grou nds that it avoids certain restrictive assumptions about preferences a nd also incorporates attitudes toward risk. The authors review the con struct of the QALY, including both the commonly used risk-neutral form ulation and the more general formulation that permits risk aversion (o r risk preference) with respect to remaining life years. They show tha t the HYE adds flexibility to the risk-neutral form of the QALY by per mitting the rate of tradeoff between life years and quality of life to depend on the life span, albeit at the cost of eliciting numerous add itional time-tradeoff assessments. However, the claim that the HYE inc orporates attitudes toward risk is incorrect, and the proposed two-sta ge procedure to measure HYEs is neither necessary nor sufficient to in corporate attitudes toward risk. In fact, the HYE assumes risk neutral ity with respect to healthy years of life and, therefore, is less suit able for decisions under uncertainty than is the general (risk-averse) form of the QALY.