1 Division of Cardiovascular Medicine, Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison.
2 Department of Internal Medicine, University of Michigan Medical School, Ann Arbor.
3 Department of Health Management and Policy, School of Public Health, University of Michigan, Ann Arbor.
4 Department of Veterans Health Service Research & Development Center for Clinical Management Research, VA Ann Arbor Healthcare System, Ann Arbor, Michigan.