1. Center for Surgical Trials and Outcomes Research (CSTOR), Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
2. International Center for Spinal Cord Injury, Hugo W. Moser Research Institute at Kennedy Krieger Institute, Baltimore, Maryland.
3. Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
4. Division of Acute Care Surgery, Department of Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland.
5. Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
6. Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland.
7. Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
8. International Neurorehabilitation Institute, Lutherville, Maryland.
9. Department of Neurosurgery, All India Institute of Medical Sciences (AIIMS), New Delhi, India.