1. Respiratory unit, Department of Medicine, Obafemi Awolowo University, Ile Ife, Nigeria
2. Neurology unit, Department of Medicine, Obafemi Awolowo University, Ile Ife, Nigeria
3. Department of Family Medicine, Obafemi Awolowo University Teaching Hospitals Complex, Ile Ife, Nigeria
4. Department of Community Health, Obafemi Awolowo University, Ile Ife, Nigeria