Intellectual Differences in Negro and White Mental Defectives
Scores of 199 Southern Negro and white children whose Full Scale IQ was 69 or below were compared for the verbal and performance tests of the WISC. A multivariate test of the hypothesis of no mean racial differences resulted in the hypothesis being rejected for both sexes. A discriminant function determined from the tests classified 73% of the original Ss into their correct racial group and 63% of a cross-validation sample of 141. Examination of the function weights and test mean differences yielded the conclusion that while the whites had the typical pattern of intellectual performance found in other studies with retardates, the score pattern for Negroes resembled that of gifted children in that their verbal test scores were generally higher than their performance test scores. Implications of this finding for diagnostic and educational procedures are mentioned.