Beginning in 1995, Krumholz also started a series of projects that revealed readmissions as a problem and tested interventions to reduce patient risk. This work placed readmission in public view and later work, with the Centers for Medicare & Medicaid Services, resulted in national measures that were publicly reported and subsequently incorporated into the Patient Protection and Affordable Care Act.
In 2004, Krumholz's work with timely treatment of heart attacks showed that only 33% of heart attack patients were receiving angioplasty within 90 minutes of their admission to the hospital. With National Institutes of Health funding, he pioneered methods to study top performers, including combining quantitative and qualitative studies that contributed to a national campaign to translate the research into action. Within three years more than 90% of patients were treated within guideline recommendations.
Krumholz credits his teams at the university, the hospital, and the Robert Wood Johnson Foundation as the force behind his contributions to the way healthcare is delivered in the United States today. Krumholz's team at CORE has expanded to include a lot of strategic research partnerships over the years, including insurers, Medicare, and the medical device and pharmaceutical industries, where he says his team is trying to make a larger difference in the market through studying best practices to influence clinical decision making.