1. Department of Neurosurgery, University of Louisville, Louisville, KY
2. Cornell University, Ithaca, NY
3. Washington University, Barnes Jewish Hospital Plaza, St. Louis, MO
4. Department of Health Management and Systems Science, School of Public Health and Information Science, University of Louisville, Louisville, KY
5. Department of Anesthesia, University of Louisville, KY
6. Providence Regional Medical Center Everett, Everett, WA