1. Department of Cornea and External Disease, Aravind Eye Care System, Madurai, India
2. Department of Ophthalmology, University of California, San Francisco, USA
3. Francis I. Proctor Foundation, University of California, San Francisco, USA
4. Department of Epidemiology & Biostatistics, University of California, San Francisco, USA
5. Institute for Global Health, University of California, San Francisco, USA