Abstract
This study investigates cognitive sex differences in child and adolescent intelligence as measured by the WISC-IV (German edition; Petermann & Petermann, 2007). It was hypothesized that there would be no differences attributable to sex in Full Scale IQ (FSIQ), but on various composite score levels. Sex effects were expected to be more pronounced during/after puberty than before. Method: The standardization sample of the German WISC-IV (N = 1650) was used to assess and evaluate sex differences in test performance across defined age groups (6–9, 10–12, and 13–16 years). Results: At all ages, there were no gender effects in the Full-Scale IQ, but gender effects favoring boys in the Verbal Comprehension Index (t = 3.94, p < .001, d = .19) and Perceptual Reasoning Index (t = 2.69, p = .007, d = .13). In the Processing Speed Index, girls scored higher than boys (t = 6.75, p < .001, d = .33). No significant sex-by-age interaction effect was found using ANOVA, but various 1-df contrasts showed substantial sex differences at specific ages. Conclusions: Results are discussed in the context of the specific constructs measured by the WISC-IV, taking into account recent findings in neurobiological and developmental psychology.
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