ObjectiveTo compare two approaches to measuring racial/ethnic disparities in the use of high-quality hospitals. Data SourcesSimulated data. Study DesignThrough simulations, we compared the minority-serving approach of assessing differences in risk-adjusted outcomes at minority-serving and non-minority-serving hospitals with a fixed-effect approach that estimated the reduction in adverse outcomes if the distribution of minority and white patients across hospitals was the same. We evaluated each method's ability to detect and measure a disparity in outcomes caused by minority patients receiving care at poor-quality hospitals, which we label a between-hospital disparity, and to reject it when the disparity in outcomes was caused by factors other than hospital quality. Principal FindingsThe minority-serving and fixed-effect approaches correctly identified between-hospital disparities in quality when they existed and rejected them when racial differences in outcomes were caused by other disparities; however, the fixed-effect approach has many advantages. It does not require an ad hoc definition of a minority-serving hospital, and it estimated the magnitude of the disparity accurately, while the minority-serving approach underestimated the disparity by 35-46 percent. ConclusionsResearchers should consider using the fixed-effect approach for measuring disparities in use of high-quality hospital care by vulnerable populations.