Evaluating quality-adjusted life years: estimation of the health utility index (HUI2) from the SF-36.
Quality-adjusted life years (QALYs) are well recognized as a valid measure for outcomes in cost-effectiveness analyses. A summary health utility score is necessary to evaluate QALYs. The objective of this study was to predict a summary utility score (represented by the Health Utility Index [HUI2]) from scores on the SF-36.


METHODS
A structural equation framework was applied to longitudinal data collected from 1992 to 1995 on a sample of patients insured by Southem California Kaiser Permanente (N = 6921). An ordinary least squares (OLS) method was used to estimate the HUI2.


RESULTS
The OLS model on cross-sectional data predicted 50.5% of the observed variance in HUI2 scores. Parameter estimates of all SF-36 components showed statistical significance at the P < 0.05 level.


CONCLUSIONS
Results of this study provide a quantitative link between two important measures of health status. The present model can be used to estimate health utility summary scores in studies that have collected SF-36 data.
Nichol
M B
MB
Pharmaceutical Economics and Policy, University of Southern California, Los Angeles 90033, USA.
Sengupta
N
N
Globe
D R
DR
D000328:Adult; D000368:Aged; D001294:Attitude to Health; D002140:California; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D019057:Quality-Adjusted Life Years; D018401:Sample Size