[1] Georgetown Univ, Sch Med, Washington, DC USA
[2] Univ Calif Los Angeles, Stein & Doheny Eye Inst, Dept Ophthalmol, Los Angeles, CA USA
[3] Thomas Jefferson Univ, Sidney Kimmel Med Coll, Philadelphia, PA USA
[4] Univ Calif Los Angeles, Fielding Sch Publ Hlth, Dept Biostat, Los Angeles, CA USA
[5] Univ Calif Los Angeles, Fielding Sch Publ Hlth, Dept Epidemiol, Los Angeles, CA USA