1. University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, United States
2. University of Muenster, Department of Neurosurgery, Muenster, Germany
3. University of Virginia, School of Medicine, Charlottesville, Virginia, United States
4. Leiden University, Medical Center, Leiden, The Netherlands
5. Harvard University, School of Medicine, Boston, Massachusetts, United States
6. Stanford University, School of Medicine, Stanford, California, United States
7. Allegheny Health Network, Pittsburgh, Pennsylvania, United States
8. University of Texas Southwestern Medical Center, Dallas, Texas, United States
9. Seattle’s Children’s Hospital, Seattle, Washington, United States
10. Saint Jude Children’s Research Hospital, Memphis, Tennessee, United States
11. Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, United States
12. The University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States
13. University of Missouri, Columbia, Missouri, United States
14. Dartmouth College, Geisel School of Medicine, Hanover, New Hampshire, United States
15. The University of Copenhagen, Copenhagen, Denmark
16. The University of New Mexico Medical Center, Albuquerque, New Mexico
17. Oregon Health & Science University, Knight Cancer Institute, School of Medicine, Portland, Oregon, United States
18. Las Palmas Del Sol Healthcare, El Paso, Texas, United States
19. National Institute of Health, Bethesda, Maryland, United States
20. University of California Davis, School of Medicine, Sacramento, California, United States
21. California Institute of Technology, Pasadena, California, United States
22. University of Illinois at Urbana-Champaign, Urbana-Champaign, United States