Prevalence and causes of visual impairment in Chinese adults in urban southern China: The Liwan Eye Study

Abstract

Objective: To assess the prevalence and causes of visual impairment and blindness in adults living in an urban area of southern China. Methods: Random cluster sampling was used to identify the adults 50 years and older living in the Liwan district of Guangzhou, China. Presenting visual acuity (PVA) with habitual correction and best-corrected visual acuity (BCVA) based on autorefraction and subjective refraction were measured using the Early Treatment Diabetic Retinopathy Study visual chart. Blindness and low vision were defined according to World Health Organization criteria. Eyes with visual impairment were assigned 1 principal cause for the impairment. Results: Visual acuity measurements w..