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Birth order?

Posted by jimcall on 02 Apr 2009 at 19:44 GMT

I was surprised the analysis did not control for--or even discuss--birth order, which has a well documented relationship to intelligence and is obviously related to parents' age. If the data allow this control, this work should be redone with the control; if not, then the article should include a discussion of how birth order might have affected the findings.

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