1. Institute for Public Health National Institutes of Health, Ministry of Health Malaysia Selangor Malaysia
2. Family Health Development Division Ministry of Health Malaysia Putrajaya Malaysia
3. Otorhinolaryngology Department Sungai Buluh Hospital, Ministry of Health Malaysia Sungai Buloh Malaysia
4. Otorhinolaryngology Departments Kuala Lumpur Hospital, Ministry of Health Malaysia Kuala Lumpur Malaysia
5. Biostatistic and Data Repository Sector National Institutes of Health Ministry of Health Malaysia Selangor Malaysia