Factor Structure of the KABC-II at Ages 5 and 6: Is It Valid in a Clinical Sample?

The factor structure of the German edition of the KABC-II for ages 5 and 6 was examined in a clinical sample. Participants were 450 children ages 5 and 6 who had been assessed due to various behavioral, emotional, or developmental disorders in five Centers for Social Pediatrics (SPCs). Confirmatory factor analyses of the standard test structure including core subtests of the Cattell-Horn-Carroll model and of the Luria model were conducted using maximum likelihood estimation. Several modified structures derived from CHC ability classifications were evaluated. Second-order factor structures corresponding to the standard test structure of the KABC-II demonstrated an adequate global fit for both theoretical models and were superior to unidimensional models. The fit of bifactor models was comparable to second-order models. In all subtests, the general factor accounted for more variance than group factors (broad abilities). However, in more than half of the subtests, unique variance explained the largest portion of the variance. The scale Learning/Glr showed a lack of convergent validity. At age 6, a model omitting subtest Rover significantly improved the fit. In the combined sample of 5- and 6-year-old children, both second-order and bifactor models with nine subtests demonstrated excellent fit.