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The survey of 140 children under 16 in two subnormality hospitals showed that 3 per cent of the children had definitely been rendered mentally handicapped as a consequence of violent abuse, and that a possible maximum total of 11 per cent might have been thus rendered mentally handicapped. In 24 per cent of the children, neglect was considered to be a contributory factor in reducing intellectual potential. Impairment of intellect from abuse and neglect, especially in those with 'vulnerable' brains due to pre-existing abnormality, may be much commoner in children than is generally realized.
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Buchanan et al. (1977) studied this question.
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