1 a Department of Ophthalmology , California Pacific Medical Center , San Francisco , California , USA.
2 b Department of Ophthalmology , Stanford University School of Medicine , Stanford , California , USA.
3 c The Francis I. Proctor Foundation, UCSF School of Medicine , San Francisco , California , USA.
4 d Center for Preventive Ophthalmology and Biostatistics and Ocular Inflammation Service, Scheie Eye Institute, University of Pennsylvania , Philadelphia , Pennsylvania , USA.
5 e Department of Ophthalmology , and Center for Clinical Epidemiology and Biostatistics, University of Pennsylvania , Philadelphia , Pennsylvania , USA.
6 f Department of Biostatistics & Epidemiology , Perelman School of Medicine, University of Pennsylvania , Philadelphia , Pennsylvania , USA , and.
7 g Centre for Ophthalmology, University Tuebingen , Tuebingen , Germany.