Screening of cataract surgery in four rural populations aged 50 years old and above in western China

To estimate the cataract surgical coverage and cataract surgery rate and to assess the visual outcome of cataract surgery among individuals aged at or over 50 years old in four rural populations from four different areas of western China. This cross-sectional study, performed during the period 2003 - 2005, used the method of cluster sampling and recruited 5562 persons aged 50 years old or above through household census. Standardized ocular examinations including visual acuity test, intraocular pressure measurement, slit-lamp and fundus examination were performed. The main outcome criteria were cataract surgical coverage, cataract surgery rate, complication rate and visual outcome after cataract surgery. Of individuals with bilateral presenting visual acuity < 6/60 due to age-related cataract, the cataract surgical coverage was 54% in Qinghai. It was the highest among these four populations. The highest cataract surgery rate (CSR) value was 1551 in Qinghai and the lowest 143 in Guangxi during the period of 200