Inspection time and intelligence in 7-yr-old children: A follow-up

Remeasures of inspection time (IT) were obtained from 30 of the 47 children reported in Nettelbeck and Young (Personality and Individual Differences, 10, 605–614, 1989). Ages ranged from 7 yr–0 months to 7–11 and Full Scale IQ (WISC-R) ranged from 93 to 142 (mean = 116.5 SD = 12.2). Correlations between IT and the WISC-R subtests, scales and factors used in the earlier study were generally statistically significant: and similar to those found earlier. The correlation between IT and Full Scale IQ was — 0.49, with those children whose IQs were below the median score of 116 again contributing more to this outcome. Similarly, the IT-IQ correlation was higher among children showing less well-directed attention in the IT task. Once again IT correlated better with Verbal IQ, supporting the hypothesis that IT is better associated with more general intellectual functioning than with specific cognitive abilities. Cross-lagged panel correlations between IT and IQ were —0.40, whether predicting IQ from IT or the reverse. Thus, there was no evidence for a causal relationship between these variables, although both may reflect a common cognitive ability factor.     

Race, social class and ability patterns on the WISC-R

The national standardization sample of whites and blacks on the Wechsler Intelligence Scale for Children—Revised (WISC-R) was the basis for a detailed analysis of the psychometric nature of racial and social class differences on the original 13 subscales of the WISC-R. The profiles of subtest scores of whites and blacks were compared directly and also after the racial groups were statistically equated on Full Scale IQ (FSIQ). Under the latter condition, the races differ only very slightly, although significantly, on some of the subtests, in ways generally contrary to popular expectations. The profile of white-black differences on the WISC-R subtests is markedly different, and negatively correlated with, the profiles of social class differences within each racial group, indicating that the pattern of racial differences is not explainable in terms of the difference in the average socio-economic status (SES) of blacks and whites. A Schmid-Leiman orthogonalized hierarchical factor analysis yields virtually identical factor structures and highly congruent factor loadings on the subtests for whites and blacks. Analysis of factor scores shows that by far the largest proportion of the variance between races is attributable to the general factor (g) common to all the subtests, whereas the group factors (verbal, performance and memory) contribute only minutely to the interracial variance. Hence the white-black differences on the diverse subtests of the WISC-R, and in the Full Scale IQ, are interpreted primarily as a difference in Spearman's g, rather than as differences in the more specific factors peculiar to particular content, knowledge, acquired skills or type of test. However, some slight but significant differences in patterns of ability also occur that are independent of g.     

Carolina Picture Vocabulary Test: validation with hearing-impaired students

When mean Carolina Picture Vocabulary Test standard scores were compared with WISC-R Performance Scale IQs significant differences were observed. The Carolina test scores were also correlated with both Performance IQs and the Performance Scale subtest scores. Most correlations were minimal as the two tests were independent; only WISC-R Picture Arrangement scores correlated significantly with Carolina scores. These outcomes coupled with the technical limitations of the Carolina raise serious questions regarding its utility for hearing-impaired children.     

Relationship of the Wechsler pre-school and primary scale of intelligence and the Stanford-Binet (L-M) in lower class children

Using 72 lower class children, concurrent validity of the WPPSI was studied employing Form L-M of the Stanford-Binet as the criterion. Correlations between SB and WPPSI were moderately high (.86 for FS, .81 for VS, .73 for PS), but the WPPSI appeared a somewhat more difficult test for the sample employed. Mean SB IQ (94.61) was higher than the mean FS (90.71), VS (89.38) and PS (93.68) IQs; it exceeded WPPSI IQ in 72% of all cases. On the WPPSI, PS IQ was significantly greater than either VS or FS IQs. Amont the WPPSI subtests, Vocabulary was significantly lower than all other subtests and Comprehension lower than Picture Completion, Mazes, and Block Design. The only significant sexual difference favored females on Similarities. For subjects whose FS IQ was below the group median IQ, relationships among each of the WPPSI scales and subtests were lower than for those subjects who scored above the median. This was particularly true for the Vocabulary, Animal House, and Picture Completion subtests.     

Relationship of scores on PPVT-R and WISC-R with special education children and youth

Comparisons of the Peabody Picture Vocabulary Test-Revised and the Wechsler Intelligence Scale for Children-Revised were made with 104 children diagnosed as learning disabled and mentally retarded. Significant but modest correlations were found between all but one of the WISC-R scaled scores (i.e., Coding) and PPVT-R standard scores, and between WISC-R IQs and PPVT-R standard scores. Significant differences were found among mean Verbal, Performance, and Full Scale IQs and mean PPVT-R standard scores. The PPVT-R standard scores underestimated WISC-R Verbal IQs by 7 points, WISC-R Performance IQs by 17 points, and WISC-R Full Scale IQs by 11 points.     

Gender differences on the WPPSI, the WISC-R, and the WPPSI-R

The WPPSI, WISC-R, and WPPSI-R were administered in a counterbalanced design to 72 children between the ages of 5 years, 10 months, 16 days, and 6 years, 7 months, and 15 days to test the hypothesis that mean verbal IQs on these scales would be higher for boys than for girls. Results indicated that the mean verbal IQs for boys were significantly (p<.05) higher than those for girls on all three scales. Also, significant (p<.05) differences favoring boys were found onVocabulary andComprehension subtests on all three scales. These differences are probably a peculiarity of these scales and may not need any elaborate theoretical explanation. However, clinical uses of verbal and performance IQ discrepancies may not justifiably ignore the examinees’ gender.     

Gender differences on the WPPSI,the WISC-R,and the WPPSI-R

The WPPSI, WISC-R, and WPPSI-R were administered in a counterbalanced design to 72 children between the ages of 5 years, 10 months, 16 days, and 6 years, 7 months, and 15 days to test the hypothesis that mean verbal IQs on these scales would be higher for boys than for girls. Results indicated that the mean verbal IQs for boys were significantly (p<.05) higher than those for girls on all three scales. Also, significant (p<.05) differences favoring boys were found onVocabulary andComprehension subtests on all three scales. These differences are probably a peculiarity of these scales and may not need any elaborate theoretical explanation. However, clinical uses of verbal and performance IQ discrepancies may not justifiably ignore the examinees’ gender.     

II. The comparability of the WISC-R and WAIS among 16-year-old EMR children

Thirty 16-year-old EMR children were administered the WAIS and WISC-R in counterbalance order to determine the comparability of the two assessment instruments. The WAIS was found to yield significantly higher Verbal, Performance, and Full Scale IQ scores. The comparisons of corresponding subtests indicate that all WAIS subtests were significantly higher than the WISC-R except Picture Completion. Correlations between corresponding WAIS and WISC-R IQ scales and subtests, however, were significant. The results suggest differences between the two instruments among children of subnormal intelligence, thus presenting the possibility that a child may be differentially classified based on the selection of the intelligence test.     

Concurrent and predictive validity of the Kaufman Assessment Battery for Children with a Navajo sample

The aim of this investigation was to examine the mean scores and predictive validity coefficients obtained from the Wechsler Intelligence Scale for Children-Revised (WISC-R), the Kaufman Assessment Battery for Children (K-ABC), and the Peabody Individual Achievement Test (PIAT). The K-ABC and the WISC-R were administered 1 week apart in counterbalanced order to 35 Navajo children aged 6–12$\text{1}\text{2}$ years (mean 8–9 years), followed 10$\text{1}\text{2}$ months later by administration of the PIAT. The K-ABC yielded an overall mean of 95.0, which is significantly higher than the WISC-R Full Scale IQ mean of 86.9. All WISC-R and K-ABC global scores correlated significantly except the WISC-R Verbal and K-ABC Nonverbal scales. The WISC-R Verbal and Full Scale IQs and all five K-ABC scales correlated significantly with the PIAT Total Test standard scores. However, the K-ABC Achievement scale correlated significantly higher with the PIAT Total Test than with the WISC-R Verbal and Full Scale IQs. The implications of these findings are discussed.     

Correlations for Wechsler Intelligence Scale for Children--Revised and the Wechsler Preschool and Primary Scale of Intelligence for Iranian children.

This study focused on the relationship between the Wechsler Intelligence Scale for Children--Revised (WISC--R) and the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) given to 40 6-yr.-old Iranian children. Pearson correlations between the WISC--R and the WPPSI IQs and between scaled scores on the corresponding subtests were significant. The comparison of mean IQs and scaled scores indicates that the WISC--R yielded a significantly higher Verbal IQ and higher scores on Information, Vocabulary, Comprehension, and Picture Completion than the WPPSI. The mean difference between corresponding Verbal and Full Scale IQs was not significant. These results suggest that scores on the two instruments correlated well for these 6-yr.-old Iranian children and the content on which IQs for the recently restandardized WISC--R and WPPSI are based are related.     

Differential construct validity of intelligence as popularly measured: Correlations of age with raw scores on the WISC-R for Blacks Whites, males, and females

Raw scores on the 12 WISC-R subtests and the verbal, performance, and full scale IQ scales were correlated with age in years separately for 938 White males, 137 Black males, 927 White females, and 153 Black females. Highest and lowest correlations from the four groups were then contrasted for each of the 15 WISC-R variables to determine whether the magnitude of the relationship between age and performance on current tests of intelligence is constant across race and sex. Regression coefficients between age and raw scores were also contrasted across groups. None of the 15 comparisons of corrections yielded differences that were statistically significant. Regression coefficients differed only with respect to the Full Scale IQ, showing smaller incremental changes with age for Black males than for other groups. The results indicated that the relationship between age and intelligence test performance is relatively constant across race and sex and supports the construct validity of the WISC-R as a measure of children's intelligence for Blacks, Whites, males, and females, though some evidence was found to indicate slower development of “g” in Black males as compared to the other groups.     

Short form and factor-analytic studies of the WISC-R with behavior problem children

Two analyses of the WISC-R protocols of 100 children referred for behavioral problems in school were conducted to study (a) the utility of a variety of WISC short forms and (b) the factor structure of the WISC-R. Although the correlations between short form and WISC-R IQs were highly significant, mean differences and a high percentage of IQ classification changes indicated that the short forms were not acceptable WISC-R substitutes. Different factor analyses consistently evidenced two factors, Verbal Comprehension and Perceptual Organization, which corresponded perfectly to the Verbal and Performance.     

Reliability and predictive validity of the WISC-R with native-American Navajos

The reliability and predictive validity of the WISC-R was examined with a sample of 40 Navajo children. Internal consistency reliability estimates of WISC-R subtests as well as composites were found to be low for the Navajo subjects as compared with the reliability coefficients reported in the WISC-R manual. Correlation coefficients between the WISC-R subtests and those of the Wide Range Achievement Test (WRAT) were low. Only the Block Design subtest correlated significantly with the WRAT-Spelling. The predictive validity of the WISC-R IQ scales was similarly found to be very low. Considering the nature and size of sample, cautions in generalizing these findings to other native-American populations are recommended.     

On the use of the WISC-R supplementary subtests as alternates

If a regularly administered WISC-R subtest cannot be administered properly or is invalidated, the manual suggests that a supplementary subtest, either Digit Span or Mazes, can serve as a substitute, but perhaps prorating the sum of scaled scores on the remaining subtests would be better. Data from the WISC-R standardization sample were analyzed to investigate the psychometric properties of these two variants of the standard procedure. Proration consistently resulted in higher validities (i.e., correlations between scores on the variant Verbal, Performance, or Full Scale and scores on the corresponding original scale), whereas substitution almost as consistently resulted in higher reliabilities, but in both cases the differences were small. Examiners may decide for themselves whether or not to use the supplementary subtests as alternates.     

An examination for construct bias in the WISC-R across socioeconomic status

The ten subtests comprising the Wechsler Intelligence Scale for Children —Revised (WISC-R) were independently factor analyzed for middle and low socioeconomic status children. Two factors described the structure of the test in both cases. These two factors corresponded quite closely to the Verbal Comprehension and Perceptual Organization factors usually reported for the WISC-R. After testing for the equivalence of covariance matrices between the two socioeconomic status groups, coefficients of congruence between the factors were calculated. These coefficients indicated equivalence in the constructs being measured across the two groups.     

Measuring fluid intelligence on a ratio scale: Evidence from nonverbal classification problems and information entropy

Drawing on the g factor and information theory literatures, the relationship between the four subtests of the Culture-Fair Intelligence Test (CFIT) and the entropy of the Ruiz Absolute Scale of Complexity Management (R-ASCM) was investigated. In results based on data collected from 186 university students, the entropy of the R-ASCM mostly loads the first principal component extracted from the CFIT subtests and shows a corresponding strong relationship with the item difficulty of the R-ASCM. Because entropy is a ratio scale of complexity&#x2014; with a true zero and units called bits&#x2014;these findings suggest that entropy is the right vehicle for measuring the information contained in nonverbal intelligence tests.     

Comparison of black-white differences on the WISC-R and the K-ABC: Spearman's hypothesis

The Kaufman Assessment Battery for Children (K-ABC) and the Wechsler Intelligence Scale for Children-Revise (WISC-R) are compared with respect to the magnitudes of the average white-black differences in standardized scaled scores and in raw scores. The two test batteries were administered to a sample of 172 fourth- and fifth-grade children comprising 86 black-white pairs matched on age, sex, school, and socioeconomic status. The K-ABC and WISC-R are highly correlated, and the general factor, or g, of one battery is virtually identical to the g of the other. The high positive correlation between the size of the white-black difference on the various subtests of both batteries and the subtests' loadings on the g factor bears out Spearman's hypothesis that a test's white-black dicriminability is a direct function of the test's g loading. The lesser white-black discriminability of the K-ABC relative to the WISC-R is attributable to (1) the smaller g loadings of the K-ABC subsets and (2) the presence of other factors, particularly sequential short-term memory which, to some degree, offsets the white-black difference in g.     

Components of IQ Scores Across Levels of Measured Ability

Forty-three (43) students from the Talent Identification Program's Summer Residential Program living in North Carolina took the Wechsler Intelligence Scale for Children—Revised (WISC-R; Wechsler, 1974) during the program. The test was also administered to 50 other North Carolina Students who qualified for the SRP but did not attend, as well as 34 students who had not been identified as gifted. The scores were evaluated for normative and idiographic strengths and weaknesses on the 12 subtests of the WISC-R. The idiographic differences were calculated by comparison against the average score of only the 6 subtests in the same subscale of the test (Verbal or Performance) as well as against all 12 subtests on the test. It was found by means of the former comparisons that the gifted students showed significantly more idiographic strengths on the Verbal scales and weaknesses on the Performance scales than the academically competent sample.     

The effects of skewness on the interpretation of ITPA scaled scores

Studied the degree to which skewed score distributions can affect the interpretation of Illinois Test of Psycholinguistic Abilities (ITPA) (Kirk, McCarthy, & Kirk, 1968) subtest scores. Indices of skewness were determined for the 10 main ITPA subtests for each of the eight age groups which comprised the normative sample (Paraskevopoulos & Kirk, 1969). The ITPA normative sample was drawn from children, both male and female, having abbreviated Stanford-Binet IQs between 84 and 116 and ranging in age from 2 years 7 months to 10 years 1 month. The results indicate that the following subtests were most seriously affected by scale limitations: auditory reception, auditory association, visual reception, manual expression, and grammatic closure. The results suggest that indices of score variability such as average deviation and standard scores must be interpreted with extreme caution when skewness is a significant factor.