1. Retina Service, Wills Eye Hospital, Philadelphia, Pennsylvania, USA
2. Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
3. Department of Biostatistics, Epidemiology & Informatics, University of Pennsylvania, Philadelphia, Pennsylvania, USA
4. Discovery Eye Center, MyungSung Christian Medical Center, MyungSung Medical School, Addis Ababa, Ethiopia
5. Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania, USA
6. Center for Clinical Epidemiology and Biostatistics, Department of Biostatistics & Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
7. Leonard Davis Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA