In adoption studies, selective placement refers to the practice by which adoption agencies tend to deliberately match certain characteristics of an adopted child's adopted parents with those of his or her biological parents. When this occurs, it results in a correlation between environments between biological relatives raised in different homes. It has the potential to bias the conclusions of such studies, because twins who were reared in separate environments may in fact have been reared in much more similar environments than assumed. This can result in an inflated estimate of heritability.[1][2][3] There is evidence that selective placement was a major confound in many early studies of twins reared apart.[4] Some adoption studies report little or no evidence of selective placement.[1][5][6][7] For example, a 1979 study by Ho et al. reported a generally low level of selective placement in adopted children for either physical or behavioral traits. The authors concluded that to the extent that selective placement occurred for such traits, "our data suggest that it is based largely on characteristics of the birth father," rather than those of the adoptee.[8] Carey (2003) concluded that selective placement was "moderate" for physical characteristics and typically "small or nonexistent" for behavioral characteristics.[9]
References
edit- ^ a b Leve, Leslie D.; Neiderhiser, Jenae M.; Ge, Xiaojia; Scaramella, Laura V.; Conger, Rand D.; Reid, John B.; Shaw, Daniel S.; Reiss, David (February 2007). "The early growth and development study: a prospective adoption design". Twin Research and Human Genetics. 10 (1): 84–95. doi:10.1375/twin.10.1.84. ISSN 1832-4274. PMC 4169207. PMID 17539368.
- ^ Kamin, Leon J.; Goldberger, Arthur S. (February 2002). "Twin Studies in Behavioral Research: A Skeptical View". Theoretical Population Biology. 61 (1): 83–95. Bibcode:2002TPBio..61...83K. doi:10.1006/tpbi.2001.1555. PMID 11895384.
- ^ Eysenck, Hans Jürgen (1979). The Structure and Measurement of Intelligence. Transaction Publishers. p. 110. ISBN 9781412839235.
- ^ Moore, David S. (2003-02-05). The Dependent Gene: The Fallacy of "Nature Vs. Nurture". Macmillan. p. 51. ISBN 9780805072808.
- ^ Price, R. A.; Cadoret, R. J.; Stunkard, A. J.; Troughton, E. (August 1987). "Genetic contributions to human fatness: an adoption study". The American Journal of Psychiatry. 144 (8): 1003–1008. doi:10.1176/ajp.144.8.1003. ISSN 0002-953X. PMID 3605421.
- ^ Miles, Donna R.; Carey, Gregory (1997). "Genetic and environmental architecture on human aggression". Journal of Personality and Social Psychology. 72 (1): 207–217. doi:10.1037/0022-3514.72.1.207. ISSN 1939-1315. PMID 9008382.
- ^ Duyme, M.; Dumaret, A.-C.; Tomkiewicz, S. (1999-07-20). "How can we boost IQs of "dull children"?: A late adoption study". Proceedings of the National Academy of Sciences. 96 (15): 8790–8794. Bibcode:1999PNAS...96.8790D. doi:10.1073/pnas.96.15.8790. ISSN 0027-8424. PMC 17595. PMID 10411954.
- ^ Ho, Hsiu-zu; Plomin, Robert; DeFries, J. C. (March 1979). "Selective placement in adoption". Social Biology. 26 (1): 1–6. doi:10.1080/19485565.1979.9988356. ISSN 0037-766X. PMID 538462.
- ^ Carey, Gregory (2003). Human Genetics for the Social Sciences. SAGE. p. 302. ISBN 9780761923459.