EVALUATION OF A POPULATION-BASED MEASURE OF QUALITY-OF-LIFE - THE HEALTH AND ACTIVITY LIMITATION INDEX (HALEX)

This paper briefly discusses the rationale and methods for developing and evaluating the Health and Activity Limitation Index (HALex), a gen eric measure of health that consists of two attributes: perceived heal th and activity limitation. Using a multiattribute utility scoring sys tem, information from these attributes was combined to form a single s core that represents health-related quality of life (QoL) on a 0.0-1.0 continuum. The construct and incremental validity are evaluated using data from a sample of over 40,000 adults who participated in the 1990 US National Health Interview Survey. The health state distributions f or known groups, defined in terms of personal or lifestyle characteris tics such as sex, age and smoking status, were comparable to those for similarly defined states that have been studied by other researchers. Of the regression models examined in this analysis, age, years of sch ooling and being in a high-risk group based on body mass index (BMI) w ere found to have the largest impact on health as measured by the HALe x. Although this measure was developed to be combined with mortality d ata to form a quality-adjusted life year (QALY) for detecting changes in the health of the US population from 1990 to 2000, it may also be u seful for inclusion in clinical studies, in particular as the national data are readily available for use as norms.