1. Department of Emergency Medicine, Stanford University, Stanford, CA 94304, USA
2. Department of Neurosurgery, Brain Performance Center, Stanford University, Stanford, CA 94304 USA
3. Carolina Sports Concussion Clinic, Cary, NC 27513, USA
4. Departments of Family Medicine, Neurology, Oregon Health & Science University, Portland, OR & Rebound Orthopedics & Neurosurgery, Portland, OR 97239, USA
5. Departments of Community Health & Family Medicine & Neurology, University of Florida, Gainesville, FL 32611, USA
6. Department of Neurosurgery, Brain Performance Center, Stanford University, Stanford, CA 94304, USA
7. UBMD Department of Orthopaedics & Sports Medicine, Jacobs School of Medicine & Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14203, USA
8. Division of Physical Medicine & Rehabilitation, University of Utah, Salt Lake City, UT 84108, USA
9. Division of Pediatric Neuropsychology, Safe Concussion Outcome Recovery & Education Program, Children’s National Health System, Departments of Pediatrics & Psychiatry & Behavioral Sciences, George Washington University School of Medicine, Rockville, MD 20850, USA