1 2(nd) Brigade Combat Team, 4(th) Infantry Division, Fort Carson, Colorado; Department of Military and Emergency Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
2 The University of Arizona College of Medicine Tucson, Tucson, Arizona. Electronic address: sam@aemrc.arizona.edu.
3 Department of Emergency Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas.
4 Departments of Emergency Medicine and Neurology, University of Michigan, Ann Arbor, Michigan.
5 Department of Emergency Medicine, Brooke Army Medical Center, Fort Sam Houston, Texas.