1. University of Maryland School of Medicine, Baltimore, Maryland
2. Wolff Center at University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
3. Department of Surgery, University of Texas Southwestern Medical Center, Dallas
4. Department of Surgery, Ohio State University Medical Center, Columbus
5. Department of Surgery, Loyola University Medical Center, Chicago, Illinois
6. Department of Surgery, Beth Israel Deaconess, Boston, Massachusetts
7. Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
8. Department of Surgery, NorthShore University Health System, Chicago, Illinois