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Alavi Y, Jofre-Bonet M, Bunce C, Wormald RP, Viswanathan A, Foster A, Hitchings R.Alavi Y, et al.Ophthalmic Epidemiol. 2011 Oct;18(5):233-43. doi: 10.3109/09286586.2011.602577.Ophthalmic Epidemiol. 2011.PMID: 21961513