1. Department of Medicine, University of Colorado, Aurora
2. Department of Surgery, University of California, Davis
3. Division of Biostatistics, University of Minnesota, Minneapolis
4. Department of Surgery, Washington University, St Louis, St Louis, Missouri
5. Department of Surgery, University of Maryland, Baltimore
6. Department of Surgery, University of Texas, Austin
7. Department of Surgery, University of California San Francisco, Fresno
8. Department of Surgery, University of Michigan, Ann Arbor
9. Department of Surgery, Medical College of Wisconsin, Milwaukee
10. Department of Surgery, Lehigh Valley Health Network, Bethlehem, Pennsylvania
11. Department of Surgery, Christiana Care Health System, Wilmington, Delaware
12. Department of Surgery, University of Texas Southwestern, Dallas
13. Department of Surgery, University of Utah, Salt Lake City
14. Department of Surgery, University of California San Diego
15. Department of Surgery, Wake Forest School of Medicine, Winston-Salem, North Carolina
16. Department of Surgery, Henry Ford Hospital, Detroit, Michigan
17. Department of Surgery, University of Southern California Los Angeles County
18. Department of Surgery, University of Texas, Houston