1. Center for Health Policy and Health Services Research (L.K.W., B.P., B.K.A., D.E.L.), Detroit, Michigan 48202
2. Department of Internal Medicine (L.K.W., D.E.L.), Detroit, Michigan 48202
3. Department of Public Health Sciences (E.L.P., K.E.W.), Henry Ford Health System, Detroit, Michigan 48202
4. Departments of Medicine (E.G.B.), San Francisco, San Francisco, California 94143
5. Bioengineering and Therapeutic Sciences (E.G.B.), University of California, San Francisco, San Francisco, California 94143