Pay for performance has become a central strategy in the drive to improve health care. We assessed the long-term effect of the Medicare Premier Hospital Quality Incentive Demonstration (HQID) on patient outcomes. We used Medicare data to compare outcomes between the 252 hospitals participating in the Premier HQID and 3363 control hospitals participating in public reporting alone. We examined 30-day mortality among more than 6 million patients who had acute myocardial infarction, congestive heart failure, or pneumonia or who underwent coronary-artery bypass grafting (CABG) between 2003 and 2009. At baseline, the composite 30-day mortality was similar for Premier and non-Premier hospitals (12.33% and 12.40%, respectively; difference, -0.07 percentage points; 95% confidence interval [CI], -0.40 to 0.26). The rates of decline in mortality per quarter at the two types of hospitals were also similar (0.04% and 0.04%, respectively; difference, -0.01 percentage points; 95% CI, -0.02 to 0.01), and mortality remained similar after 6 years under the pay-for-performance system (11.82% for Premier hospitals and 11.74% for non-Premier hospitals; difference, 0.08 percentage points; 95% CI, -0.30 to 0.46). We found that the effects of pay for performance on mortality did not differ significantly among conditions for which outcomes were explicitly linked to incentives (acute myocardial infarction and CABG) and among conditions not linked to incentives (congestive heart failure and pneumonia) (P=0.36 for interaction). Among hospitals that were poor performers at baseline, mortality was similar in the two groups of hospitals at the start of the study (15.12% and 14.73%; difference, 0.39 percentage points; 95% CI, -0.36 to 1.15), with similar rates of improvement per quarter (0.10% and 0.07%; difference, -0.03 percentage points; 95% CI, -0.08 to 0.02) and similar mortality rates at the end of the study (13.37% and 13.21%; difference, 0.15 percentage points; 95% CI, -0.70 to 1.01). We found no evidence that the largest hospital-based pay-for-performance program led to a decrease in 30-day mortality. Expectations of improved outcomes for programs modeled after Premier HQID should therefore remain modest.
