Multiattribute and Single-Attribute Utility Functions for the Health Utilities Index Mark 3 System

BACKGROUND: The Health Utilities Index Mark 3 (HUI3) is a generic multiattribute preference-based measure of health status and health-related quality of life that is widely used as an outcome measure in clinical studies, in population health surveys, in the estimation of quality-adjusted life years, and in economic evaluations. HUI3 consists of eight attributes (or dimensions) of health status: vision, hearing, speech, ambulation, dexterity, emotion, cognition, and pain with 5 or 6 levels per attribute, varying from highly impaired to normal. OBJECTIVES: The objectives are to present a multiattribute utility function and eight single-attribute utility functions for the HUI3 system based on community preferences. STUDY DESIGN: Two preference surveys were conducted. One, the modeling survey, collected preference scores for the estimation of the utility functions. The other, the direct survey, provided independent scores to assess the predictive validity of the utility functions. MEASURES: Preference measures included value scores obtained on the Feeling Thermometer and standard gamble utility scores obtained using the Chance Board. RESPONDENTS: A random sample of the general population (> or =16 years of age) in Hamilton, Ontario, Canada. RESULTS: Estimates were obtained for eight single-attribute utility functions and an overall multiattribute utility function. The intraclass correlation coefficient between directly measured utility scores and scores generated by the multiattribute function for 73 health states was 0.88. CONCLUSIONS: The HUI3 scoring function has strong theoretical and empirical foundations. It performs well in predicting directly measured scores. The HUI3 system provides a practical way to obtain utility scores based on community preferences.