1. Department of Emergency Medicine, Duke University Medical Center, Durham, NC, USA
2. Durham County Emergency Medical Services, Durham, NC, USA
3. ESO Solutions, Austin, TX, USA
4. Wake County Emergency Medical Services, Raleigh, NC, USA
5. Department of Emergency Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
6. Division of Geriatrics, Department of Medicine, Duke University Medical Center, Durham, NC, USA