1. Department of Ophthalmology, Dongguk University Ilsan Hospital, Goyang, Korea
2. Department of Ophthalmology, Soonchunhyang University Cheonan Hospital, Cheonan, Korea
3. Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea
4. Department of Ophthalmology, Seoul National University Boramae Hospital, Seoul, Korea
5. Department of Biostatistics, Seoul National University Boramae Hospital, Seoul, Korea