1. Department of Emergency Medicine, The Warren Alpert Medical School, Brown University, Providence, Rhode Island.
2. Department of Health Services, Policy and Practice, Brown University School of Public Health, Providence, Rhode Island.
3. Research Department, Providence VA Medical Center, Providence, Rhode Island.
4. Center for Gerontology and Healthcare Research, Brown University School of Public Health, Providence, Rhode Island.
5. Department of Emergency Medicine, University of Colorado School of Medicine, Aurora, Colorado.