IQ similarity in monozygotic and dizygotic twin children: effects of the same versus different examiners: a research note.
The Wechsler Intelligence Scale for Children--Revised was administered to two independently identified samples of monozygotic (MZ) and dizygotic (DZ) twin children. Co-twins in the first sample were tested by the same examiner, while co-twins in the second sample were tested by different examiners. IQ intraclass correlations were similar for the two MZ twin samples (.84 and .88), and identical for the two DZ twin samples (.54). The implications of this analysis are discussed with reference to twin study methodology, research on IQ similarity and replication of child development research.
Segal
N L
NL
University of Minnesota, Department of Psychology, Minneapolis 55455.
Russell
J
J
D002648:Child; D005260:Female; D006801:Humans; D007360:Intelligence; D008297:Male; D015588:Observer Variation; D014429:Twins, Dizygotic / Q000235:genetics* / Q000523:psychology; D014430:Twins, Monozygotic / Q000235:genetics* / Q000523:psychology; D014888:Wechsler Scales / Q000706:statistics & numerical data