1. Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, Washington.
2. Department of Pediatrics, University of Washington, Seattle, Washington.
3. Harborview Injury Prevention and Research Center, University of Washington, Seattle, Washington.
4. Department of Rehabilitation Medicine, University of Washington, Seattle, Washington.
5. Department of Epidemiology, University of Washington, Seattle, Washington.
6. Department of Rehabilitation Psychology, Seattle Children's Hospital, Seattle, Washington.
7. Department of Biostatistics, University of Washington School of Public Health, Seattle, Washington.
8. Department of Neurological Surgery, University of Washington, Seattle, Washington.
9. Department of Emergency Medicine, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.