Intelligence test performance of Indian children as a function of type of test and age.

Abstract

The systematic effect of environment on intelligence tesc performance makes it difficult to obtain unbiased estimates of intellectual capacity. Even seemingly universal tasks such as the drawing of a human figure have proven susceptible to cultural bias (Anastasi, 1960a, Chs. 8, 9; 1960b, Ch. 8; Goodenough & Harris, 1950; McCarthy, 1944). In the absence of culture-free tests, accurate estimates of intellectual capacity depend on knowledge of the effects of particular environments. Relatively little adjustment for environment is necessary prior to school age. At later ages performance may vary widely with S's background, particularly on language tests (Anastasi, 1960a, Chs. 6, 8). The present paper reports observations made on a culturally isolated group of Fox Indian children. Measures of intelligence were obtained from school children of different ages using tests which employed language, nonlanguage, and drawing tasks. The performance of Indian groups exceeds rhe general norms on drawing tests (Havighurst & Gunther, 1946), equals the norms on non-language tests, and is below the norm on language tests (Havighursr & Hilkevitch, 1944; Jameison & Sandiford, 1928). Wheeler ( 1942) reported that the intellectual performance of Tennessee mountain children, who show a tesc pattern similar to that of Indians, approaches the national norm with increasing time in school. It was expected that the present study would confirm the past findings and extend them in the following manner. (a) At the earliest school age language performance (as expressed in IQ equivalents) would be below average, and both non-language and drawing IQs would be average or above; (b) the average IQs of all tests would approach the general norms when older groups were measured; and (c) measures of more specific factors of intellect would follow a pattern similar to that for the IQs. PROCEDURE Stlbjects.-Ss were Fox Indian children from the Tama reservation in central Iowa. 36 Ss were randomly selected from the reservation school roster of 86 children. There were 6 boys and 6 girls from each of three age groups which conformed to a 2-yr. classroom arrangement as follows: (a) Group I (Grades 1 and 2) had a mean age of 7 yr., 3 mo. with a range of 6 yr., 5 mo. to 8 yr., 2 mo.; (b) Group I1 (Grades 3 and 4) had a mean age of 9 yr., 6 mo. and a range of 8 yr., 5 mo. to 10 yr., 7 mo.; and (c) Group 111 (Grades 5 and 6) had a mean age of 11 yr., 9 mo. and a range of 10 yr., 9 mo. to 12 yr., 9 mo.