What makes some children short-sighted?
D000293:Adolescent; D000328:Adult; D000818:Animals; D002648:Child; D006801:Humans; D008027:Light / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000209:etiology*; D011932:Reading; D012160:Retina / Q000503:physiopathology