英语翻译麻烦英语高手将下面一段话翻译成英文,目的 调查重庆市城乡50岁及以上人群白内障患病率,手术率,白内障盲人手术覆盖

Purpose
To investigate the differences among the rates of the cataract victims,surgical operations,surgical operation coverage of the blind caused by cataract and the social costs of the blind caused by cataract with the target research group being on the 50 years old or over who reside in the urban and rural areas of Chongqing City and to therefore provide data basis for the treatment of the cataract victims.