1. Metro Pain Group, Victoria, Australia
2. Muskuloskelettales Zentrum - Interventionelle Schmerztherapie, Krankenhaus Neuwerk “Maria von den Aposteln,” Mönchengladbach, Germany
3. Jax Spine & Pain Centers, Jacksonville, Florida
4. Louisiana Pain Specialists, New Orleans, Louisiana
5. New Orleans East Hospital, New Orleans, Louisiana
6. Department of Anesthesiology and Pain Medicine, University of California San Diego Health Sciences, La Jolla, California
7. Veterans Administration San Diego Healthcare System, San Diego, California
8. The Spine and Nerve Center of the Virginias, Charleston, West Virginia
9. Institute for Neuromodulation, Boca Raton, Florida
10. Ainsworth Institute of Pain Management, New York, New York, USA