1. Department of Emergency Medicine Massachusetts General Hospital Boston Massachusetts USA
2. University of Michigan Medical School Ann Arbor Michigan USA
3. University of Washington School of Public Health Seattle Washington USA
4. Department of Emergency Medicine University of Michigan Ann Arbor Michigan USA
5. Washtenaw/Livingston Medical Control Authority Ann Arbor Michigan USA
6. Department of Internal Medicine University of Michigan Ann Arbor Michigan USA
7. Institute for Healthcare Policy and Innovation University of Michigan Ann Arbor Michigan USA