Recalculation of Data: In the Original Contribution entitled “Relationship Between Medicare's Hospital Compare Performance Measures and Mortality Rates” published in the December 13, 2006, issue of JAMA (2006;296:2694-2702), a normal distribution of the expected mortality rate was assumed during the creation of the statistical model that estimated the relationship between the expected mortality rate and performance and a linear model was used; however, the expected mortality rate should have been transformed using a logit transformation, which makes the transformed expected mortality rate normally distributed and does not violate the assumptions of using a linear model. In the abstract on page 2694, the second, third, and fourth sentences under Results should be “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 (P = .003), 0.007 for 30-day mortality (P = .002), and 0.012 for 1-year mortality (P<.001). For the heart failure performance measures, the absolute mortality reduction was smaller, ranging from 0.001 for inpatient mortality (P = .08) to 0.002 for 1-year mortality (P = .23). For the pneumonia performance measures, the absolute reduction in mortality ranged from 0.003 for 30-day mortality (P = .15) to 0.007 for 1-year mortality (P = .02).” On page 2696, third column, first paragraph, the second to last sentence should be “We estimated the relationship between each hospital's risk-adjusted mortality rate and performance, while controlling for other hospital characteristics.” On page 2698, second column, first full paragraph, the first and last sentences should be “Across all AMI 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, 0.007 for 30-day mortality, and 0.012 for 1-year mortality. For the pneumonia performance measures, the absolute reduction in mortality ranged from 0.003 for 30-day mortality to 0.007 for 1-year mortality.” Also on that page, Table 3 should appear as shown and should replace the previously published table.