1 Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama.
2 Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, Alabama.
3 Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama. Electronic address: [email protected].