1. The Warren Alpert Medical School of Brown University, Providence, RI, USA
2. Rhode Island Hospital, Providence, RI, USA
3. The Miriam Hospital, Providence, RI, USA
4. Norman Prince Neurosciences Institute, Providence, RI, USA
5. Mayo Clinic, Rochester, MN, USA
6. Johns Hopkins University School of Medicine, Baltimore, MD, USA
7. Northwestern University Feinberg School of Medicine, Chicago, IL, USA
8. Icahn School of Medicine at Mount Sinai, New York, NY, USA
9. Cleveland Clinic, Cleveland, OH, USA
10. Toronto Western Hospital, Toronto, Ontario, Canada
11. Kansas University Medical Center, Kansas City, KS, USA
12. Columbia University, New York, NY, USA
13. The Spine Hospital at NY-Presbyterian/Allen, New York, NY, USA