[1] Inst Oftalmol Conde Valenciana, Dept Cornea & Cirugia Refract, Mexico City, DF, Mexico
[2] Inst Nacl Salud Publ, Ctr Invest Sistemas Salud, Cuernavaca, Morelos, Mexico
[3] Hosp Gen Dr Manuel Gea Gonzalez, Dept Otorrinolaringol, Mexico City, DF, Mexico
[4] Inst Oftalmol Conde Valenciana, Dept Segmento Anterior, Mexico City, DF, Mexico
[5] Inst Oftalmol Conde Valenciana, Dept Epidemiol Ocular & Salud Visual, Chimalpopoca 14, Mexico City 06800, DF, Mexico
[6] Secretaria Salud Mexico, Direcc Gen Adjunta Epidemiol, Mexico City, DF, Mexico