1. UPMC Sports Concussion Program, University of Pittsburgh, Pittsburgh, Pennsylvania
2. Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
3. Landstuhl Regional Medical Center, Landstuhl, Germany
4. Defense and Veterans Brain Injury Center, Silver Spring, Maryland
5. UPMC Sports Medicine Concussion Program, Altoona, Pennsylvania
6. Office for Sport Concussion Research, Department of Health, Human Performance, & Recreation, University of Arkansas, Fayetteville