1. Vivian L. Smith Center for Neurologic Research, Department of Neurosurgery, University of Texas–Houston Medical School, Houston, Texas
2. Departments of Biostatistics and Neurosurgery, Medical College of Virginia/Virginia Commonwealth University, Richmond, Virginia
3. Department of Physical Medicine and Rehabilitation, Baylor College of Medicine, Houston, Texas
4. Department of Neurosurgery, St. Louis University, St. Louis, Missouri
5. Department of Neurological Surgery, University of California, Davis, Sacramento, California
6. Brain Trauma Research Center, Department of Neurosurgery, University of Pittsburgh, Pittsburgh, Pennsylvania
7. Division of Neurosurgery, Indiana University, Indianapolis, Indiana