1. School of Medicine, Georgetown University, Washington, District of Columbia, USA;
2. Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, USA;
3. Department of Neurosurgery, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA;
4. Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA;
5. Department of Neurosurgery, Muhimbili Orthopaedic Institute, Dar es Salaam, Tanzania;
6. Department of Neurosurgery, Kilimanjaro Christian Medical Centre, Moshi, Tanzania;
7. Department of Neurosurgery, George Washington University School of Medicine and Health Sciences, Washington, District of Columbia, USA;
8. Department of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona, USA;
9. Department of Neurosurgery, Carle Foundation Hospital, Urbana, Illinois, USA