. Author manuscript; available in PMC: 2010 Sep 1.

Published in final edited form as: Behav Genet. 2009 Jul 21;39(5):532–540. doi: 10.1007/s10519-009-9283-y

Table 3.

Biologically related and adoptive sibling correlations (95% confidence intervals)

Behavioral factor	Biologically related (N = 130)	Adoptive (N = 246)
Academic achievement	0.25^* (0.08, 0.41)	0.02 (–0.11, 0.15)
Total IQ	0.46^* (0.31, 0.58)	0.21^* (0.09, 0.33)
Substance use disorders	0.30^* (0.13, 0.45)	0.22^* (0.10, 0.34)
Externalizing disorders	0.33^* (0.16, 0.47)	0.25^* (0.13, 0.37)
Internalizing disorders	0.29^* (0.12, 0.45)	0.22^* (0.10, 0.34)
Peer groups	0.34^* (0.18, 0.48)	0.13^* (0.01, 0.25)
Disinhibitory behavior	0.33^* (0.17, 0.48)	0.22^* (0.10, 0.34)
Negative emotionality	0.24^* (0.07, 0.40)	0.09 (–0.04, 0.21)

All sibling pairs are like-sex and all behavioral variables, with the exception of Total IQ, were age-sex corrected prior to analysis

95% Confidence intervals that do not include 0. Adopted Sibling correlations were unchanged when corrected for range restriction due to parental education level and disinhibitory behavior problems