1. Hai Yen Vision Institute, Ho Chi Minh City, Vietnam;
2. Francis I. Proctor Foundation, University of California, San Francisco, CA;
3. Department of Ophthalmology, University of California, San Francisco, CA;
4. Department of Epidemiology and Biostatistics, University of California, San Francisco, CA; and
5. Institute for Global Health Sciences, University of California, San Francisco, CA.