1. Department of Surgery, Irrua Specialist Teaching Hospital, PMB 8, Irrua, Nigeria
2. Department of Community Medicine, Imo State University Teaching Hospital, PMB 8, Orlu, Nigeria
3. Department of Surgery, University of Maiduguri Teaching Hospital, PMB 1414, Maiduguri, Nigeria
4. Department of Surgery, University College Hospital, PMB 5017, Ibadan, Nigeria