Measuring Racial Disparities in the Quality of Ambulatory Diabetes Care

BACKGROUND: Improving the health of minority patients who have diabetes depends in part on improving quality and reducing disparities in ambulatory care. It has been difficult to measure these components at the level of actionable units. OBJECTIVE: To measure ambulatory care quality and racial disparities in diabetes care across groups of physicians who care for populations of ambulatory diabetes patients. RESEARCH DESIGN: Prospective cohort analysis using administrative data. SUBJECTS: Using fee-for-service Medicare claims data from 2003 to 2005, we link patients to their principal ambulatory care physician. The patients are then linked to the hospital where their physicians work or have their patients admitted, creating physician-hospital networks. MEASURES: Proportion of recommended diabetes testing received by black and nonblack diabetes patients. RESULTS: Blacks received 70% of recommended care compared with nonblacks who received 76.9% (P