1. Walter Reed National Military Medical Center, Bethesda, Maryland, USA
2. Uniformed Services University of the Health Sciences, Bethseda, Maryland, USA
3. Ohio State University Wexner Medical Center, Columbus, Ohio, USA
4. Johns Hopkins University, Baltimore, Maryland, USA
5. Sibley Memorial Hospital, Washington DC, USA
6. University Colorado School of Medicine, Aurora, Colorado, USA
7. Atrium Health, Charlotte, North Carolina, USA
8. Mayo Clinic, Jacksonville, Florida, USA