Sex differences in latent cognitive abilities ages 5 to 17: Evidence from the Differential Ability Scales—Second Edition

Sex differences in the latent general and broad cognitive abilities underlying the Differential Ability Scales, Second Edition were investigated for children and youth ages 5 through 17. Multi-group mean and covariance structural equation modeling was used to investigate sex differences in latent cognitive abilities as well as changes in these differences across age. Most broad abilities showed mean differences across the sexes, and all such differences varied across ages. Girls showed an advantage on the processing speed (Gs) first-order residual factor. Girls also showed advantages at some ages on free-recall memory, a narrow ability of long term retrieval (Glr). Boys showed a developmentally-related advantage on a visual-spatial ability (Gv) first-order residual factor, depending on age. Younger girls showed an advantage on short-term memory (Gsm). No statistically significant sex differences were shown on the latent comprehension-knowledge (Gc) factor, or on a second-order, latent g factor. Boys showed larger variances for several broad abilities, some substantial, but those differences were not statistically significant.     

Measurement invariance of WISC-IV across normative and clinical samples

Measurement invariance of the WISC-IV second-order factorial structure between normative and clinical samples was investigated using WISC-IV core subtests and a total of 1100 children aged 6-16. Multi-group higher order analysis of mean and covariance structure (MG-MACS) models were used to analyze these data. Results supported measurement invariance. Only Coding and Comprehension subtest intercepts varied slightly between groups. The hypothesized WISC-IV factor model described the data well. Factor patterns, first- and second-order factor loadings, intercepts, residual variances of measured subtests, and disturbances of first-order factors of the WISC-IV were generally invariant. Results suggested that WISC-IV index scores and subtests have the same meaning for children in both normative and clinical groups.