Non-equivalence of WPPSI, WPPSI-R, and WISC-R scores

The WPPSI-R, WISC-R, and WPPSI were administered in a counterbalanced design to 72 children, between the ages of 5 years, 11 months and 6 years, 8 months, in order to determine their equivalence by testing the equality of means, variances, and covariances based on scaled scores and IQs. The results indicated that the three scales were not equivalent with respect to any of the IQs because they did not meet one or more of the criteria. The relative magnitudes of the mean IQs on the three scales were in accord with the predicted order: highest IQs on WPPSI, next highest on WISC-R, and the lowest on WPPSI-R. Results were discussed in the context of the secular inflation in IQs and the corresponding compensatory deflation built into the normative data of the new versions.     

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.     

Concurrent validity of the WISC-R factor scores

This study investigated the efficacy of predicting academic achievement as measured by the Wide Range Achievement Test using the factor scores of the Wechsler Intelligence Scale for Children-Revised as potential predictors. Both instruments were administered to 200 school children referred for psychological evaluations. Factor scores for the WISC-R were computed according to equations provided by Gutkin (1978). These factor scores then were regressed in a stepwise manner on the Reading, Spelling, and Arithmetic standard scores from the Wide Range Achievement Test. Stepwise regressions also were performed using the traditional Verbal and Performance IQs as the potential predictors. A comparison was made between the results obtained by use of the factors or the more common scores. The results indicated that the Freedom From Distractibility factor score significantly aided in the prediction of Reading and Spelling achievement and was of primary importance in predicting Arithmetic achievement. When the stepwise results using the different scores were contrasted, the factor scores accounted for appreaciably more variance in Arithmetic than did the traditional Verbal and Performance IQs. Derived regression equations are reported along with a discussion of the interpretability of the Freedom From Distractibility factor.     

Interpreting the WPPSI subtests scores of language impaired children--a structural approach

The problem of characterising more specifically the cognitive requirements involved in subtests from standardised measures of intelligence represents a main problem in the research on exceptional populations. Seventy-five specifically language impaired (SLI) preschool children and 49 normally developing children were administered the Wechsler Preschool and Primary Scale of Intelligence (WPPSI). The scaled scores on the WPPSI were categorised according to Bannatyne's suggested regrouping to determine whether the pattern Spatial > Conceptual > Sequential could be observed in the data. The predicted pattern was only partially confirmed for language impaired children. The scaled scores on the WPPSI were then recategorized according to their structural complexity. Since structurally complex tasks contain more categories than the structurally simpler tasks, the pattern structurally Simple > Moderate > Complex was predicted and confirmed for language impaired children. Furthermore, it was hypothesized that the structurally Complex categories would discriminate better between language-impaired children and normally developing children than any other recoded categories. This hypothesis was confirmed. The low scores obtained by language impaired children on structurally Complex categories were interpreted as the result of capacity limitations in information processing rather than a deficit of any particular mental ability.     

A microcomputer program for evaluating WISC-R factor scores

A data analysis routine was developed for the Apple II series microcomputer that allows school psychologists to quickly calculate WISC-R factor scores and evaluate the significance of differences between the factors and individual subtest deviations within the Verbal Comprehension and Perceptual Organization factors. The source code written in Applesoft BASIC is provided. With minor modifications the program can be adapted to run on other computer systems.     

Comparison of WISC and WISC-R scores of referred black,white and Latino children

Seventy-two school psychologists in the tri-state area of Michigan, Illinois and Ohio administered both the WISC and WISC-R to 164 black, white and Latino children in a counterbalanced order with a specific test-retest interval of not less than a week or more than a month. These children had been referred to the school psychologist because of concerns about their intellectual ability. Significant WISC/WISC-R differences were found, with the WISC-R yielding lower results. These results have implications for test users, special education programs, and mainstreaming efforts.     

Stability of WISC-R scores for a sample of learning disabled children

The study was designed to assess the stability of WISC-R profiles of 36 learning disabled children given the WISC-R two times. The mean time between tests was 2.5 yr. The pattern reported for learning disabled children on Bannatyne's categories was evident for the group at both times, however, this pattern was not found for the majority of subjects. Analysis indicated a decrease over time in Verbal IQs, Full Scale IQs, and Bannatyne's Conceptual category, confirming previous findings. Possible reasons for the changes in scores are discussed.     

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.     

Three-year stability of WISC-R factor scores for black and white, female and male children classified as learning-disabled

Wechsler Intelligence Scale for Children-Revised (WISC-R) test and retest scores for a homogeneous sample (N=322) of approximately equal numbers of black and white, female and male learning-disabled children were compared over 3 years for factor structure and factor structure stability. These analyses were also conducted with a subsample (N=229) of the total sample for whom Digit Span scores were available. The socioeconomic status of children in the sample was determined by parents' occupation. The results suggested that WISC-R factor structure was stable over 3 years. Two-and three-factor solutions were found for the total group; three factors were found when Digit Span was included in the analysis. Coefficients of congruence indicated factorial similarity between groups of black and white, female and male children classified as learning-disabled.     

Interpreting the WISC-R subtest scores of reading impaired children—a structural approach

The problem of characterising more specifically the cognitive requirements involved in subtests from standardised measures of intelligence represents a main problem in the research on exceptional populations. A new way of classifying tests of mental abilities is presented. Rather than focusing on the content of a given test, the present classification system focuses on their structures. The classification system is applied to the WISC-R (Wechsler Intelligence Scale for Children—Revised, Wechsler, 1974). It will be used to interpret the IQ-profiles of a clinically defined sample of reading impaired children (N=82). The basic finding of the study is that the structural complexity of a subtest influences the tests results of reading impaired children. This influence is interpreted as a consequence of poor procedural knowledge; i.e., poor knowledge about how to organise complex sets of data. It is suggested that teaching of metacognitive strategies could be an aid for reading impaired children.     

I. Validity of WISC-R factor scores in predicting achievement and attention for four sociocultural groups

The predictive validity of WISC-R factor scores was examined with samples from the four sociocultural groups of Anglo, Black, Chicano, and native American Papago. The Full Scale IQ and Verbal Comprehension (VC) factor scores were significantly better predictors of achievement as measured by teacher ratings and the Metropolitan Achievement Test. The Perceptual Organization and Freedom from Distractibility (FD) factor scores were also significantly related to achievement, but at a lower level than Full Scale and VC. The correlations of the WISC-R and achievement measures were nearly the same for three of the four groups (exception was native American Papago). The relationship of the FD factor score to ratings of attention was statistically significant, but relatively low. Cautions in interpreting FD as a measure of attention were recommended due to overlap of distributions and low proportion of variance in attention accounted for by FD.     

Effect of socioeconomic status of biological and adoptive parents on WISC-R subtest scores of their French adopted children

Analyses from an a priori full cross-fostering study (Capron & Duyme, 1989, 1991), investigating the IQs of 38 children whose average age was 168 (SE = 3.28) months, indicated a link between the socioeconomic status (SES) of both biological and adoptive parents and Full, Verbal, and Performance IQs of the WISC-R scale. Here detailed analyses of the WISC-R scale are presented. These show that these two factors affect Block Design and Information subtests, and other subtests are affected either by one or the other factor. Two subtests—Picture Arrangement and Picture Completion—are not affected by either factor. There is no evidence for an interaction between these factors on adopted children's subtest scores. As the sample size is small for a test of nonadditivity, the analysis is extended to the power of interaction test.     

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.     

The effect of a commercial game on children's block design scores on the WISC-R IQ test

Two experiments investigated the extent to which 10-year old children's scores on the WISC-R Block Design subtest were affected by prior experience with a specific commercial game that involved blocks and matching patterns. Experiment 1 found that 12 10-year old children who happened to have experience with the particular commercial game scored approximately three scaled score points higher on the WISC-R Block Design subtest than 24 matched children without game experience. In Experiment 2, 24 children who did not have prior experience with this particular commercial game were randomly assigned either to a Game condition (involving two 15-minute sessions with the game) or to a No-Game condition (which involved no further game experience). Children in the Game condition subsequently increased their WISC-R Block Design scores more than children in the No-Game condition. Taken together, the experiments indicate that relatively brief interactions with a commercial game can cause a significant improvement in children's performance on an IQ subtest.     

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.     

WPPSI reliability and predictive validity with disadvantaged Mexican-American children

The reliability and predictive validity of the WPPSI was investigated with a sample of lower SES Mexican-American children. Reliability was determined using split-half procedures parallel to those reported in the test manual. Predictive validity was determined by correlating WPPSI scores with scores from the Metropolitan Reading Test. The results revealed that the WPPSI has high reliability, as determined by internal consistency procedures, but validity coefficients were not significant. These results suggest that the WPPSI may be inappropriate for special program placement purposes with this population.