Age differences in WISC-III subtests of children experiencing academic difficulties

WISC-III subtest scores of 180 children referred because of academic difficulties were analyzed for differences based on age (M = 9.6, SD = 2.7) and IQ. Rank-orders of all subtests indicated no significant correlations across the six age-IQ groups, suggesting that interpretation of changes in subtest rankings may require consideration of age and IQ, especially for such children. When data were organized into Acquired Knowledge, Spatial Ability, and speed-related task categories, analyses of variance showed a main effect for IQ. Furthermore, scores on Acquired Knowledge were associated with age at the lower category of IQ, whereas Spatial Ability and speed-related tasks were not related to age.