1. Concussion Research Lab, Department of Kinesiology, The University of Georgia, Athens, Georgia, USA
2. Inova Sports Medicine Concussion Program, Department of Orthopaedics & Sports Medicine, Inova Medical Group, Fairfax, Virginia, USA
3. Office for Sport Related Concussion Research/Department of Health, Human Performance and Recreation, The University of Arkansas, Fayetteville, Arkansas, USA
4. Department of Orthopaedic Surgery, The University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA