1. Department of Otorhinolaryngology Head and Neck Surgery, Federal University of Health Sciences, Azare, Nigeria
2. Department of Otorhinolaryngology Head and Neck Surgery, Abubakar Tafawa Balewa University Teaching Hospital, Bauchi, Nigeria
3. Department of Medicine, Abubakar Tafawa Balewa University Teaching Hospital, Bauchi, Nigeria
4. Department of Otorhinolaryngology, Modibbo Adama University Teaching Hospital, Yola, Nigeria