1. Department of Emergency Medicine, Maine Medical Center, Portland, Maine, USA.
2. Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.
3. Department of Emergency Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA.
4. Department of Emergency Medicine, Aventura Hospital and Medical Center, Aventura, Florida, USA.
5. Department of Emergency Medicine, Brigham and Women's Faulkner Hospital, Boston, Massachusetts, USA.