1. Center for Health Professions Education, Uniformed Services University, Bethesda, MD 20814-4712, USA
2. The Henry M Jackson Foundation for the Advancement of Military Medicine, Inc, 6720A Rockledge Dr, Bethesda, MD 20817, USA
3. Department of Health, Human Function, and Rehabilitation Sciences, The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA