1. Department of Physical Medicine and Rehabilitation, Indiana University School of Medicine, Indianapolis, Indiana.
2. Rehabilitation Hospital of Indiana, Indianapolis, Indiana.
3. Department of Physical Medicine and Rehabilitation, Carolinas Rehabilitation, Carolinas HealthCare System, Charlotte, North Carolina.
4. TIRR Memorial Hermann, Houston, Texas.
5. Spaulding Rehabilitation Hospital, Boston, Massachusetts.
6. Department of Rehabilitation Medicine, University of Washington, Seattle, Washington.
7. Department of Physical Medicine and Rehabilitation, The Ohio State University, Columbus, Ohio.
8. Department of Physical Medicine and Rehabilitation, University of Texas Southwestern Medical Center, Dallas, Texas.
9. Department of Neurological Surgery, University of Washington, Seattle, Washington.
10. Department of Biostatistics, University of Washington, Seattle, Washington.