Relationship between Medicare's hospital compare performance measures and mortality rates.
BACKGROUND
In response to concerns about the quality of care in US hospitals, the Centers for Medicare & Medicaid Services began measuring hospital performance and reporting this performance on their Web site, Hospital Compare. It is unknown whether these process performance measures are related to hospital-level outcomes.


OBJECTIVE
To determine whether quality measured with the process measures used in Hospital Compare are correlated with and predictive of hospitals' risk-adjusted mortality rates.


METHODS
Cross-sectional study of hospital care between January 1 and December 31, 2004, for acute myocardial infarction, heart failure, and pneumonia at acute care hospitals in the United States included on the Hospital Compare Web site. Ten process performance measures included in Hospital Compare were compared with hospital risk-adjusted mortality rates, which were measured using Medicare Part A claims data.


METHODS
Condition-specific inpatient, 30-day, and 1-year risk-adjusted mortality rates.


RESULTS
A total of 3657 acute care hospitals were included in the study based on their performance as reported in Hospital Compare. Across all acute myocardial infarction performance measures, the absolute reduction in risk-adjusted mortality rates between hospitals performing in the 25th percentile vs those performing in the 75th percentile was 0.005 for inpatient mortality, 0.006 for 30-day mortality, and 0.012 for 1-year mortality (P<.001 for each comparison). For the heart failure performance measures, the absolute mortality reduction was smaller, ranging from 0.001 for inpatient mortality (P = .03) to 0.002 for 1-year mortality (P = .08). For the pneumonia performance measures, the absolute reduction in mortality ranged from 0.001 for 30-day mortality (P = .05) to 0.005 for inpatient mortality (P<.001). Differences in mortality rates for hospitals performing in the 75th percentile on all measures within a condition vs those performing lower than the 25th percentile on all reported measures for acute myocardial infarction ranged between 0.008 (P = .06) and 0.018 (P = .008). For pneumonia, the effects ranged between 0.003 (P = .09) and 0.014 (P<.001); for heart failure, the effects ranged between -0.013 (P = .06) and -0.038 (P = .45).


CONCLUSIONS
Hospital performance measures predict small differences in hospital risk-adjusted mortality rates. Efforts should be made to develop performance measures that are tightly linked to patient outcomes.
Werner
Rachel M
RM
Center for Health Equity Research and Promotion, Philadelphia Veterans Affairs Medical Center, Philadelphia, Pa, USA. rwerner@mail.med.upenn.edu
Bradlow
Eric T
ET
D019985:Benchmarking; D002303:Cardiac Output, Low / Q000401:mortality / Q000628:therapy; D003430:Cross-Sectional Studies; D017052:Hospital Mortality; D006761:Hospitals / Q000592:standards* / Q000706:statistics & numerical data; D006801:Humans; D033181:Information Dissemination; D006278:Medicare / Q000592:standards*; D009203:Myocardial Infarction / Q000401:mortality / Q000628:therapy; D010043:Outcome and Process Assessment, Health Care; D011014:Pneumonia / Q000401:mortality / Q000628:therapy; D019984:Quality Indicators, Health Care; D020379:Risk Adjustment; D014481:United States