1 Section of Cardiac Surgery, Yale School of Medicine, New Haven, Conn; Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Conn.
2 Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Mass; Center for Quality and Safety, Massachusetts General Hospital, Harvard Medical School, Boston, Mass.
3 Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Conn.
4 Department of Health Care Policy, Harvard Medical School, Boston, Mass; Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, Mass.
5 Section of Cardiac Surgery, Yale School of Medicine, New Haven, Conn.
6 Center for Outcomes Research and Evaluation, Yale-New Haven Hospital, New Haven, Conn; Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, Conn; Department of Health Policy and Management, Yale School of Public Health, New Haven, Conn. Electronic address: harlan.krumholz@yale.edu.