Improvements in the Distribution of Hospital Performance for the Care of Patients With Acute Myocardial Infarction, Heart Failure, and Pneumonia, 2006–2011

BACKGROUND: Medicare hospital core process measures have improved over time, but little is known about how the distribution of performance across hospitals has changed, particularly among the lowest performing hospitals. METHODS: We studied all United States hospitals reporting performance measure data on process measures for acute myocardial infarction, heart failure, and pneumonia to the Centers for Medicare & Medicaid Services (CMS) from 2006–2011. We assessed changes in performance across hospital ranks, variability in the distribution of performance rates, and linear trends in the 10(th) percentile (lowest) of performance over time for both individual measures and a created composite measure for each condition. RESULTS: More than 4,000 hospitals submitted measure data each year. There were marked improvements in hospital performance measures (median performance for composite measures: acute myocardial infarction: 96% to 99%, heart failure: 85% to 98%, pneumonia: 83% to 97%). A greater number of hospitals reached the 100% performance level over time for all individual and composite measures. For the composite measures, the 10(th) percentile significantly improved (acute myocardial infarction: 90% to 98%, P