[Epidemiological study of mental retardation in Nanjing].
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000453:epidemiology*; D008297:Male; D012737:Sex Factors