Differential validity of the K-ABC for lower functioning preschool children versus those of higher ability

The Kaufman Assessment Battery for Children (K-ABC) and the Stanford-Binet Intelligence Scale, Form L-M, were administered to 93 preschool children at risk for learning problems. Lower and higher functioning groups were determined by a Stanford-Binet IQ median split. Although the Stanford-Binet and K-ABC yielded nearly identical results in the higher group, K-ABC standard scores were significantly higher than Stanford-Binet IQ in the lower group. The Stanford-Binet and K-ABC correlated more strongly in the higher group than in the lower group. These findings question the ability of the K-ABC to discriminate among at-risk preschoolers functioning in the lower ranges of cognitive ability.