title: Survey of familial correlations in measured intellectual functions.
mesh_terms: D000328:Adult; D000367:Age Factors; D002648:Child; D002668:Child Rearing; D004522:Educational Status; D004777:Environment; D005190:Family; D005191:Family Characteristics; D005260:Female; D005826:Genetics, Medical; D006801:Humans; D007360:Intelligence; D008297:Male; D011247:Pregnancy; D012737:Sex Factors; D012801:Sibling Relations; D014427:Twins