1. Allen Foster Community Eye Health Research Centre, International Centre for Advancement of Rural Eye care, L V Prasad Eye Institute, L V Prasad Marg, Banjara Hills, Hyderabad 500 034, India
2. Bausch & Lomb School of Optometry, L V Prasad Eye Institute, Hyderabad 500 034, India
3. Dana Center for Preventive Ophthalmology, Wilmer Eye Institute at Johns Hopkins University, Baltimore, MD 21287, USA
4. School of Optometry & Vision Science, University of New South Wales, Sydney 2033, Australia
5. Community Health & Nutrition Office, Area Hospital, Kandukur, Prakasam District, Andhra Pradesh 523105, India