Transracial adoption meta-analysis: Van Ijzendoorn et al (2005)

Van Ijzendoorn, M. H., Juffer, F., & Poelhuis, C. W. K. (2005). Adoption and cognitive development: a meta-analytic comparison of adopted and nonadopted children’s IQ and school performance. Psychological bulletin, 131(2), 301. It turns out that someone already did a meta-analysis of adoption studies and cognitive ability. It does not solely include cross-country transracial, but…

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Transracial adoption study: Odenstad et al (2008)

I found this one a long time ago and tweeted it, but apparently forgot to blog it. Odenstad, A., Hjern, A., Lindblad, F., Rasmussen, F., Vinnerljung, B., & Dalen, M. (2008). Does age at adoption and geographic origin matter? A national cohort study of cognitive test performance in adult inter-country adoptees. Psychological Medicine, 38(12), 1803-1814….

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Transracial adoption study: Bruce et al (2009)

Introduction This is a post in the on-going series of comments on studies of international/transracial adoption. A global genetic/hereditarian model of cognitive differences and their socioeconomic effects implies that adoptees from different populations/countries/regions should show the usual group differences in the above mentioned traits and outcomes, all else equal. All else is of course not…

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Transracial adoption study: Stams et al, 2000

This is another relatively small international adoption study. 159 children were adopted in homes in the Netherlands from Sri Lanka, Korea and Colombia. Participants are described as: The present study examines the development and adjustment of 159 adopted children at age 7 years. The largest group, 129 adopted children, was selected from 2 studies, starting…

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Transracial adoption study: Lindblad et al, 2003

As Jason Malloy has mentioned, it is strange that in the race intelligence debates, people usually cite the same few studies over and over: Shortly after writing that post, I decided that more needed to be written about transracial adoption research as a behavior genetic experiment. Arthur Jensen, Richard Lynn, and J. Philippe Rushton have…

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