AA Yekta, A Fotouhi, M Khabazkhoob, H … - Ophthalmic Epidemiology, 2009 - informahealthcare.com Purpose: To determine the prevalence rates of refractive errors in elderly
people in Mashhad, Iran. Methods: In a cross-sectional study with a cluster
sampling method, the sample population was selected proportionate to the ... Related articles - All 5 versions
SA Schellini, SR Durkin, E Hoyama, F Hirai, … - BMC ophthalmology, 2009 - biomedcentral.com A population-based cross-sectional study was conducted involving a random start
point and then systematic sampling of an urban Brazilian population in the city
of Botucatu. There were approximately 3 300 individuals aged 1 to 91 years ... Related articles - Cached - All 6 versions