1. From the Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University and Beijing Ophthalmology and Visual Science Key Laboratory, Beijing, China; 2Handan Eye Hospital, Hebei Province, China; 3Wilmer Eye Institute, Johns Hopkins Univer
2. Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland; 4Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; and
3. From the Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University and Beijing Ophthalmology and Visual Science Key Laboratory, Beijing, China;
4. Handan Eye Hospital, Hebei Province, China;
5. School of Public Health, Peking University, Beijing, China.