An epidemiologic survey of senile cataract in China.
D000328:Adult; D000368:Aged; D002386:Cataract / Q000453:epidemiology* / Q000209:etiology; D002681:China; D006801:Humans; D008875:Middle Aged; D013472:Sunlight / Q000009:adverse effects; D014466:Ultraviolet Rays / Q000009:adverse effects