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A critical analysis of IQ studies of adopted children

Richardson, K and Norgate, SH 2006, 'A critical analysis of IQ studies of adopted children' , Human Development, 49 (6) , pp. 319-335.

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The pattern of parent-child correlations in adoption studies has long been interpreted to suggest substantial additive genetic variance underlying variance in IQ. The studies have frequently been criticized on methodological grounds, but those criticisms have not reflected recent perspectives in genetics and developmental theory. Here we apply those perspectives to recent IQ adoption studies and show how they further question two sets of problems: first, the assumption of additive gene and environmental effects; second, the assumption that the adoption situation approximates a randomized-effects design. We show how a number of possible factors having systematic effects in breach of those assumptions can produce the received pattern of correlations without appealing to unusual amounts of additive gene variance.

Item Type: Article
Uncontrolled Keywords: Adoption, development, intelligence, IQ
Themes: Subjects / Themes > H Social Sciences > HQ The family. Marriage. Woman > HQ503 The family. Marriage. Home > HQ0767 Children. Child development
Subjects / Themes > R Medicine > R Medicine (General)
Health and Wellbeing
Subjects outside of the University Themes
Schools: Schools > School of Health Sciences > Centre for Health Sciences Research
Schools > School of Nursing, Midwifery, Social Work & Social Sciences > Centre for Nursing, Midwifery, Social Work & Social Sciences Research
Journal or Publication Title: Human Development
Publisher: S. Karger AG, Basel
Refereed: Yes
ISSN: 0018716X
Depositing User: H Kenna
Date Deposited: 03 Aug 2007 10:35
Last Modified: 30 Nov 2015 23:49

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