1. Guangdong Eye Institute, Department of Ophthalmology, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
2. Shantou University Medical College, Shantou, China
3. Southern Medical University, Guangzhou, China
4. Statistics Office, Information and Statistics Center, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China