1. Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
2. Department of Ophthalmology, Hospital Queen Elizabeth, Sabah, Malaysia
3. Department of Ophthalmology, Hospital Kuala Lumpur, Kuala Lumpur, Malaysia
4. Department of Ophthalmology, Hospital Serdang, Selangor, Malaysia
5. Department of Ophthalmology, Faculty of Medicine, Universiti Sultan Zainal Abidin, Terengganu, Malaysia