1. Sina Trauma and Surgery Research Center, Tehran University of Medical Sciences, Tehran, Iran
2. Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
3. Department of Management, Faculty of Social Sciences and Economics, Alzahra University, Tehran, Iran
4. Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
5. Division of Spine and Peripheral Nerve Surgery, Departments of Neurological and Orthopedic Surgery, Thomas Jefferson University, Philadelphia, PA, USA
6. Department of Neurosurgery, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
7. Universal Scientific Education and Research Network (USERN), Tehran, Iran
8. Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran