The 2012 report includes 620 hospitals, designated as Top Performers on Key Quality Measures™, that are leading the way nationally in using evidence-based care processes closely linked to positive patient outcomes. The hospitals identified as attaining and sustaining excellence in accountability performance in 2011 represent approximately 18 percent of Joint Commission-accredited hospitals reporting core measure performance data. The annual report also summarizes the performance of more than 3,300 Joint Commission accredited hospitals on 45 accountability measures of evidence-based care processes closely linked to positive patient outcomes. While the data show impressive gains in hospital quality performance, improvements can still be made. Some hospitals perform better than others in treating particular conditions.