A study of mental subnormality in childhood.
D002648:Child; D000013:Congenital Abnormalities / Q000150:complications; D004641:Emigration and Immigration; D004739:England; D005190:Family; D005260:Female; D006306:Health Surveys; D006801:Humans; D008607:Intellectual Disability / Q000453:epidemiology* / Q000209:etiology; D007361:Intelligence Tests; D008297:Male