Comparison of the WPPSI, Stanford-Binet, and McCarthy Scales as Predictors of First-Grade Achievement

Abstract

35 white, middle-class children, aged 6 to 6½ yr., were tested on the WPPSI, Stanford-Binet, and the new McCarthy Scales of Children's Abilities (MSCA). Of these children 31 were tested 4 mo. later on the Metropolitan Achievement Tests (1970 Edition) at the end of first grade. The Stanford-Binet IQ and MSCA General Cognitive Index (GCI) correlated significantly with overall first-grade achievement ( p = .01) as did the MSCA Quantitative and Perceptual-Performance Scale Indexes. The WPPSI Full Scale IQ correlated with achievement ( p = .05). The mean Stanford-Binet IQ was discrepant with the children's average scores on the WPPSI, MSCA, and Metropolitan; the implications of this finding were discussed. The fact that the new scales correlated at least as well as the two more established tests, for the present group, suggests that the new battery may be useful as a predictor of school success.