1. Department of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, Massachusetts, USA.
2. Spaulding Rehabilitation Hospital and Spaulding Research Institute, Charlestown, Massachusetts, USA.
3. MassGeneral Hospital for Children Sports Concussion Program, Boston, Massachusetts, USA.
4. Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Charlestown, Massachusetts, USA.
5. Department of Psychology, University of Houston, Houston, Texas, USA.
6. Priority Research Centre for Stroke and Brain Injury, School of Medicine and Public Health, University of Newcastle; Hunter New England Local Health District Sports Concussion Program, Calvary Mater Hospital, Newcastle, New South Wales, Australia.