1 Department of Emergency Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center Boston, Rosenberg 2, One Deaconess Road, Boston, MA, 02215, USA.
2 Department of Emergency Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center Boston, Rosenberg 2, One Deaconess Road, Boston, MA, 02215, USA. sgrossma@bidmc.harvard.edu.