Non-verbal intelligence and Native-American Navajo children: A comparison between the CTONI and the WISC-III

Abstract

This study investigated the validity of the Comprehensive Test of Nonverbal Intelligence (CTONI) as a measure of intelligence for use with Native-American learning disabled students. Forty boys and ten girls between the ages of 7 and 16 and who are Native-American Navajo students with a learning disability in reading and/or mathematics participated in this study. Each participant was administered the CTONI, the WISC-III, and the WIAT. The results from this study indicated that the CTONI exhibited less variability among its composite IQ scores than the WISC-III. The CTONI and the WISC-III Full-scale IQ, Verbal IQ and Performance IQ correlate moderately. The CTONI and WISC-III are significantly predictive of reading achievement but account for less than 11% of the common variance. Yet, the CTONI and the WISC-III are moderately correlated with mathematics achievement. Factor Analytic Results suggest that the factorial structures of the CTONI and the WISC-III for this sample of Native-American students are consistent with the factorial structures proposed by the respective test authors. The CTONI appears to be a valid measure of intelligence for use with Native American populations. The implications of the findings of the CTONI with Native-American populations are discussed.