1. Department of Economics, University of Notre Dame, Notre Dame, Indiana
2. Department of Health Care Policy, Harvard Medical School, Boston, Massachusetts
3. Department of Medicine, Massachusetts General Hospital, Boston
4. National Bureau of Economic Research, Cambridge, Massachusetts
5. Department of Health Policy and Management, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
6. Division of General Internal Medicine and Primary Care, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts