Normal Children's Performance on the McCarthy Scales, Kaufman Assessment Battery, and Peabody Individual Achievement Test

Abstract

The aim of this study was to examine the relationship between the McCarthy Scale of Children's Abilities and the Kaufman Assessment Battery for Children for a sample of 51 normal children. Results revealed no significant difference between the McCarthy General Cognitive Index and the K-ABC Mental Processing Composite (t = .55, p > .10), and these scores correlated significantly (r = .55, p = .001). The predictive validity of these instruments was examined using the Peabody Individual Achievement Test (administered after a three-month interval). Multiple regression analyses revealed that the K-ABC Achievement scale was the best predictor of PIAT Total scores (R = .75), and none of the remaining K-ABC or McCarthy scales added significantly to the prediction. Implications of these and other findings are discussed.