[An epidemiologic study of mental retardation (author's transl)].
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D011247:Pregnancy