[1] Univ London London Sch Hyg & Trop Med, Dept Epidemiol & Publ Hlth, London WC1E 7HT, England
[2] Queens Univ Belfast, Dept Ophthalmol, Belfast, Antrim, North Ireland
[3] Queens Univ Belfast, Ctr Clin & Populat Sci, Belfast, Antrim, North Ireland
[4] Univ E Anglia, Ctr Environm Risk, E Anglia, England
[5] Univ Amsterdam, Acad Med Ctr, Dept Ophthalmol, Netherlands Inst Neurosci,KNAW, NL-1105 AZ Amsterdam, Netherlands
[6] Erasmus MC, Dept Epidemiol & Biostat, Rotterdam, Netherlands
[7] Natl Inst Hlth Dev, Dept Epidemiol & Biostat, Tallinn, Estonia
[8] Haukeland Sykehus Univ Bergen, Bergen, Norway
[9] Univ De Creteil, Clin Ophthalmol, Paris, France
[10] Univ Verona, Clin Oculist, I-37100 Verona, Italy
[11] Aristotle Univ Thessaloniki, Sch Med, Dept Ophthalmol, GR-54006 Thessaloniki, Greece
[12] Univ Miguel Hernandez, Dept Salud Publ, Alicante & CIBER Epidemiol & Salud Publ CIBERESP, Altea, Spain