1. Department of Family Medicine, University of Michigan, Ann Arbor, MI, USA
2. Department of Emergency Medicine, University of Michigan, Ann Arbor, MI, USA
3. Acute Care Research Unit, Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor, MI, USA
4. RAND Corporation, Santa Monica, CA, USA
5. Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
6. Alpena Fire Department/Alpena County Emergency Medical Services, Alpena, MI, USA
7. RAND Corporation, Pittsburgh, PA, USA
8. Saint Joseph Mercy Hospital, Ann Arbor, MI, USA