Factor analysis of the wisc-r and the wrat with a referral population

Scores on the WISC-R and the WRAT from a referral sample of 250 children, ages 6 through 11, were factor analyzed using a principal factor method with varimax rotation. Results offered support for interpretation of WISC-R scores in terms of Verbal and Performance scales, and for interpretation of WRAT scores as a separate achievement factor. The contention that achievement and intelligence tests measure identical constructs is challenged.