1. Washington University School of Medicine, Department of Anesthesiology, St. Louis, Missouri; Washington University School of Medicine, Department of Emergency Medicine, St. Louis, Missouri
2. Washington University School of Medicine, St. Louis, Missouri
3. Washington University, Center for Health Economics and Policy at the Institute for Public Health, St. Louis, Missouri
4. Medstar Health Research Institute, Division of Healthcare Delivery Research, Hyattsville, Maryland; Georgetown University School of Medicine, Department of Medicine, Washington, DC
5. Washington University School of Medicine, Division of Pulmonary Critical Care Medicine, Department of Medicine, St. Louis, Missouri
6. Washington University in St. Louis, Brown School, St. Louis, Missouri
7. Washington University School of Medicine, Department of Emergency Medicine, St. Louis, Missouri