Black patients have poorer outcomes on quality of care measurements in Medicare health plans

Black patients in Medicare managed care health plans often have poorer outcomes for treatment of common and important conditions such as high blood pressure, diabetes or high cholesterol, compared to white patients, according to a study in the October 25 issue of JAMA.

Eliminating disparities in health care is a fundamental component of the agenda to improve quality, according to background information in the article. Several performance reporting systems now report publicly on aspects of quality such as surgical outcomes, adherence to evidence-based quality measures, and patients' assessments of care, but few public reports about the quality of health care organizations have also assessed the equity of care provided by those organizations. Since 1997, all health plans participating in Medicare have reported on the quality of care using Health Plan Employer and Data Information Set (HEDIS) performance measures developed by the National Committee for Quality Assurance. The relationship between overall quality of care and racial disparities in quality has not been well studied.

Amal N. Trivedi, M.D., M.P.H., of Brown University, Providence, R.I., and colleagues at Harvard Medical School, conducted a study using multivariable models to assess variations among Medicare health plans in overall quality and racial disparity in 4 HEDIS outcome measures. The study sample included 431,573 individual-level observations in 151 Medicare health plans from 2002 to 2004. The researchers analyzed the outcome measures for hemoglobin A1c (a measurement of glucose) for enrollees with diabetes; low-density lipoprotein cholesterol levels for enrollees with diabetes or after a coronary event; and blood pressure levels for enrollees with hypertension.

The average performance on all 4 HEDIS outcome measures was significantly lower for black enrollees than white enrollees, with absolute percentage point differences ranging from 6.8 percent for blood pressure control to 14.4 percent for LDL-C control after a coronary event. For each measure, more than 70 percent of the racial disparity was attributable to within-plan disparity (different outcomes within the same health plan for white and black enrollees) and a much smaller proportion was due to between-plan disparity (disproportionate enrollment of black enrollees in lower-performing plans). Health plans varied substantially in both overall quality and racial disparity on each of the 4 outcome measures.

"The quality of care for Medicare managed care enrollees as assessed by HEDIS outcome measures is less than optimal, variable across health plans, and unequal by race. We observed no consistent relationship between overall performance and racial disparity in these outcome measures. High-quality health plans had racial disparities that were generally comparable in magnitude to low-quality plans, and only 1 plan demonstrated both high quality and low disparity for more than 1 outcome indicator. Furthermore, nationally observed racial disparities in outcomes were largely attributable to different outcomes for black and white enrollees within the same health plan rather than differences in the distribution of black and white enrollees across health plans," the authors write.

"Effective measurement within health plans is one cornerstone of improving quality and reducing racial disparities in outcomes. Such an approach is especially salient because health plans have both the fiduciary responsibility to enrollees to assure high-quality and equitable care and the management infrastructure to organize efforts to achieve these related goals. For the Medicare program, plan-specific performance reports that include information on equity would capture a dimension of quality not currently assessed by the HEDIS reporting system," the researchers conclude.


(JAMA. 2006;296:1998-2004. Available pre-embargo to the media at

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Last reviewed: By John M. Grohol, Psy.D. on 30 Apr 2016
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