[1] Capital Med Univ, Beijing Tongren Hosp, Beijing Tongren Eye Ctr, Beijing Inst Ophthalmol, Beijing, Peoples R China
[2] Capital Med Univ, Beijing Childrens Hosp, Ctr Clin Epidemiol & Evidence Based Med, Beijing, Peoples R China
[3] Univ Warmia & Mazury, Olsztyn, Poland
[4] Inst Res Ophthalmol, Poznan, Poland