A short-form version of the WISC-R for the learning disabled

This study investigated the best short form version of the WISC-R for learning disabled (LD) students. The WISC-R was administered to 234 LD and 290 children who were referred for psychological evaluation but were found not eligible (NE) for special education services from 45 school districts in Michigan. Stepwise multiple regressions were calculated to ascertain the best tetrads of Full Scale IQ (FS IQ) for the two groups. For the NE sample, Vocabulary, Picture Arrangement, Picture Completion, and Information were the best four indicators of FS IQ, accounting for about 80% of the variance in Full Scale scores. For the LD sample, the best four predictors of FS IQ were Similarities, Block Design, Picture Completion, and Vocabulary, accounting for about 80% of criterion variance. Using the WISC-R standardization data, Sattler identified the Information, Vocabulary, Comprehension, and Block Design subtests as one of the best short form versions for predicting FS IQ. For the LD sample of the present study, Sattler's composite yielded a multiple R of .873 with FS IQ, whereas our best four predictors yielded a multiple R of .896. It appears that Sattler's tetrad is about as good a predictor of FS IQ for LD students as that found in the present data.     

Diagnostic Utility of the Bannatyne WISC‐III Pattern

Regrouping Wechsler Intelligence Scale for Children‐Third Edition (WISC‐III) subtests into Bannatyne's spatial, conceptual, and sequential patterns has been thought by many to identify children with learning disabilities (LD). This study investigated the prevalence and diagnostic utility of WISC‐III Bannatyne patterns by comparing 1,302 children with LD to 2,158 children in the WISC‐III normative sample. Further analysis was conducted on a subsample of students with specific reading disabilities. Results indicated that the presence of the Bannatyne WISC‐III pattern would not lead to decisions that are useful in differentiating children with LD from children without LD. For example, receiver operating characteristic (ROC) analysis, measured by the area under the curve (AUC), indicated that the Bannatyne WISC‐III pattern exhibited low diagnostic utility (AUC = 0.54–0.55). Due to its inaccuracy, use of the Bannatyne WISC‐III pattern is not recommended.     

WISC-III correlations with the WIAT

Correlations between WISC-III IQs and Index scores with the eight achievement subscales of the WIAT were investigated for a sample of 202 students with specific learning disabilities, 115 students with mental retardation, and 159 students who failed to qualify for special education services (total N = 476). Corrected correlations between the WISC-III Full Scale IQ and WIAT subtests indicated differences with the correlations reported in the WIAT manual. Interestingly, our relationships were generally higher than those previously reported. Only on one subtest, Basic Reading, were significantly lower correlations than those reported in the WIAT manual present. Correlations between the Verbal Comprehension and Perceptual Organization Index scores and WIAT subtests were almost all lower than those calculated between the Verbal and Performance IQs and WIAT subtests. Implications are discussed, especially those involving the use of correlations between ability and achievement measures in regression formulas.     

Sex differences on the WISC-R for retarded children and youth

This study investigated sex differences on the WISC-R subtests for retarded males and females who were matched in terms of WISC-R Full Scale IQs. The sample consisted of 126 children and youth (63 females, 63 males) ranging in chronological age from 7–3 to 8–3, with a mean CA of 7–8. Each subject was matched in terms of Full Scale IQ score. A 2 × 10 analysis of variance with repeated measures on a single factor was used to analyze the data. Students' T and Fisher's F ratios were calculated, and differences between subtest means were analyzed by Newman-Keuls test for sample effects. Evidence from the investigation indicated that a significant interaction effect existed between sex and subtest scores.     

Testing: Exploring the WISC‐III as a measure of giftedness∗

This study investigated patterns of WISC‐III IQ subtest scores for gifted children. Subtest scatter of WISC‐III scores occurred with greater frequency in a gifted sample than for subjects reported in the test manual's normative sample. Variability from the subtest mean of the gifted was most evident on Similarities, Comprehension, Coding, and Symbol Search. The extent of subtest scatter and its pattern on the WISC‐III was similar to typical patterns of highs and lows found for gifted children on the WISC‐R with one notable exception. There was a marked lack of strength in Block Design, previously seen as a peak subtest for gifted students when assessed with the WISC‐R.     

Correlations between WISC-R subtests and verbal,performance, and full scale IQ scores for minority group children

The relationship between WISC-R subtest scores and Verbal, Performance, and Full Scale IQs was investigated for a sample comprised of rural Appalachian children. The sample was comprised of both white and black children who might be described as culturally different by virtue of low family income and residence in the mountainous areas of Virginia and North Carolina. Data analysis consisted of computing product-moment correlations (rs) between each of the ten subtests and the Verbal, Performance, and Full Scale IQs. Correlations between individual subtests and the FS IQ ranged from.49 through.63, but none of the differences between these rs were large enough to attain significance. Correlations between the verbal subtests and Verbal IQ ranged from.64 for Comprehension up to.78 for Vocabulary. For the performance subtest, the rs ranged from.54 between Coding and the Performance IQ up to.72 for Object Assembly.     

Gender differences in cognitive abilities of learning-disabled females and males

Gender differences in level and pattern of cognitive abilities were examined in 28 LD college-able females (CA 18–25) as compared to 21 LD college-able males (CA 18–25). Both groups were in the average IQ range as measured by the Wechsler Adult Intelligence Scale, with LD males significantly higher on the Full Scale IQ and three out of the four subtests, Picture Completion, Block Design, and Information. The LD females performed significantly better on the Digit Symbol subtest. The hierarchies of subtest performance and Bannatyne and ACID category scores were compared. LD females have strengths in visual-motor abilities and verbal conceptualization, while the LD males’ highest abilities were nonverbal visual-spatial confirming earlier studies on younger LD individuals and non-LD males and females. Performance on the Digit Symbol subtest was the next to the lowest for the males, the highest for females. However, for both groups, short-term and long-term memory for digits and factual knowledge and mental arithmetic problem solving were relative weaknesses. Results indicate different patterns of cognitive abilities in LD females and males which have implications for identification, service, and prognosis for the learning disabled, especially females.     

WISC-R patterns for learning disabled children at three SES levels

WISC-R and socioeconomic status (SES) data were collected on 122 learning disabled (LD) children who had been assigned to self-contained LD classrooms. The children were divided into three groups on the basis of family SES: high, middle, and low. Three questions were explored: (a) Is there a relationship between SES and IQ test scores among LD-labeled children? (b) Is the pattern of subtest scores independent of SES level? (c) Is the Verbal-Performance IQ test score discrepancy independent of SES level? Results supported affirmative answers to all three questions. Discussion centered around the implications of these results for future research on the utility of the WISC-R for diagnostic purposes.     

High-School Subjects as Conditioners of College Success

Abstract

This study examines the utility of the Ban- natyne recategorization system in discriminating among three groups of handicapped students. A stepwise discriminant functions analysis was performed on the subtest scaled scores from the WISC-R for 294 learning disabled (LD), 36 educably mentally retarded (EMR), and 71 emotionally disturbed (ED) students. The results of this analysis revealed that 100 percent of the EMR and ED students were predicted to be labeled LD on the basis of this recategorization, while 99.7 percent of the LD students were predicted to be LD. These findings are examined in relation to the use of alternative statistical methods and different diagnostic procedures to identify and classify students.     

The role of sex differences in the referral process as measured by the Peabody Picture Vocabulary Test-Revised and the Wechsler Intelligence Scale for Children-Revised

The Peabody Picture Vocabulary Test-Revised (PPVT-R) and the Wechsler Intelligence Scale for Children-Revised (WISC-R) are two tests that are often used in the assessment process for special education referrals. Sex differences apparent in these tests were examined in a sample of Arkansas school children who were first-time referrals for a psychological evaluation. The subjects' PPVT-R standard scores, WISC-R IQ scores, and WISC-R subtest scores were divided into groups according to one-year intervals from ages 6 through 16. A separate 2 × 11 (subjects' sex x subjects' age) analysis of variance was performed for each dependent variable. Results indicated significant sex differences among WISC-R Full Scale, Verbal, and Performance IQs and PPVT-R standard scores (p < .01). Several WISC-R subtests also revealed significant sex differences. Further significant sex differences were indicated at several age groups on each dependent variable, with males consistently scoring higher than females on 87%. of the dependent measures excluding the WISC-R subtest Coding, on which females scored higher. Implications concerning the referral process are discussed.     

An operational definition of learning disabilities (cognitive domain) using WISC full scale IQ and peabody individual achievement test scores

An operational index of discrepancy to assist in identifying learning disabilities (LD) in the cognitive domain was derived using the Full Scale IQ, Wechsler Intelligence Scale for Children (Wechsler, 1949, and relevant subtest scores on the Peabody Individual Achievement Test (PIAT) (Dunn and Markwardt, 1970. The index was applied to all legally identified LD children (N = 60) of a Michigan county who were in the LD program (1% of the total elementary school population of 6000 children). Of the 50 males and 10 females (mean age: 9 years 2 months; mean IQ: 91), the index identified 74% and 30% respectively as may be LD in the cognitive domain. This comprised 67% of the 60 children, or 2/3 of 1 % of the total elementary school population. Of the 67% may be LD children, 93% had discrepancy low PIAT subtest scores in Reading Recognition, 88% in Reading Comprehension, 83% in Spelling, and 52% in Arithmetic. Considerable caution should be exercised when classifying children, especially females, as LD.     

An exploratory factor analysis of the cognitive functioning of first-year bachelor students with dyslexia

An increasing number of students with dyslexia register in higher education. As a consequence, information on their pattern of strengths and weaknesses is essential to construct adequate assessment and diagnostic protocols. In a sample of 100 first-year bachelor students with dyslexia and 100 control students, a large pool of cognitive skills were tested using a variety of tests. When we applied an exploratory factor analysis to scores, a model with ten factors fitted the data best. Effect sizes were used to express the processing costs of students with dyslexia. The factors related to reading, spelling, flashed orthography, phonology, naming, math, and reading fluency resulted in large effect sizes. A factor combining all measures for crystallized IQ had a medium effect size. The subtests for fluid intelligence were divided in two separate constructs. Relationships between all subtest scores are visualized and interpreted in a general theoretical and practical framework.     

Discrepancies between IQ and index scores for a clinical sample of students: Useful diagnostic indicators?

Discrepancies between IQ and Index scores on the WISC-111 were investigated for a sample of students with SLD (n = 202), with MR (n = 115), and evaluated but not classified (n=159). Mean Verbal and Performance IQ discrepancies, though significantly different for each sample, were smaller than those reported in the WISC-III manual for the normative sample. Similarly, the Index score comparisons indicated differential functioning for the three samples, with the exception of the Verbal Comprehension and Freedom from Distractibility Index discrepancy. Moreover, the Performance IQ was higher than the Verbal IQ for all three samples. Consistent with the WISC-R literature, discrepancies between Verbal and Performance IQs and higher Performance than Verbal IQs are not diagnostic indicators of abnormalities.     

Common WISC-III examiner errors: Evidence from graduate students in training

Sixty WISC-III protocols, administered by graduate students in training, were examined to obtain preliminary data on the frequency and types of administration and scoring errors that examinees commit. Results were compared with previous studies that have evaluated examiner errors on the Wechsler scales. In general, the present results were consistent with those of previous studies that have illustrated that a large number of scoring errors are committed by graduate students as well as by other professional groups. The majority of errors committed by participants in this study were general errors. That is, errors were not specific to a particular subtest. The five most frequent errors included failure to query, failure to record responses verbatim, reporting Full Scale IQ incorrectly, reporting Verbal IQ incorrectly, and adding individual subtest scores incorrectly. However, the traditional difficult to score Verbal subtests were not as troublesome for examiners in this study as they were for examiners in previous studies. In addition, significant decreases in the mean number of errors per protocol and in the number of most frequently occurring errors per protocol were noted. © 1998 John Wiley & Sons, Inc.     

Relationship between WISC-R and WRAT in children referred for learning difficulties

Correlations between the WISC-R Full, Verbal, Performance, and Freedom from Distractibility Scale IQs, WISC-R subtest scaled scores, and Wide Range Achievement Test Reading, Spelling, and Arithmetic standard scores were computed for a sample of 114 children (64 boys, 50 girls), aged 6 to 16 years, who were referred for psychological evaluation because of academic or learning difficulties. The Full Scale IQ, Verbal Scale IQ, and Freedom from Distractibility IQ correlated moderately with the three achievement area standard scores (rs of .48 to .59). However, the Performance Scale IQ correlated minimally with reading and spelling scores (rs of .26 and .27), but moderately with arithmetic scores (r = .40). The results support the concurrent validity of the WISC-R.     

Stability of WISC-R subtest profiles for learning disabled children

Stability of the WISC-R subtest profile for 161 learning disabled (LD) children over a 7-month test-retest interval was examined. A unique subtest profile reported earlier (Smith, Coleman, Dokecki, & Davis, 1977a) was replicated. Performance IQ was significantly greater than Verbal IQ at both testing occasions. A mean test-retest increase was observed for Performance IQ, but not for Verbal IQ.     

Subtest scatter and Kaufman regroupings on the WISC-R in non-learning-disabled and learning-disabled children

The present study was undertaken to examine scatter analysis and Kaufman regroupings of WISC-R scores. Thirty-one non-learning-disabled children (NLD) and 29 learning-disabled children (LD) determined by individual IQ and achievement scores served as subjects. Scatter indices were computed within the Verbal and Performance subtests as well as between the Verbal and Performance IQ scales. Also, the regrouping categories proposed by Kaufman (1979) were examined. A significant difference in Verbal and Performance IQs was found between the LD and NLD group. Significantly more students in the LD group exhibited the Kaufman regrouping pattern than in the NLD group (p < .01). These results suggest that Kaufman regroupings and Verbal-Performance scatter analysis may be used to assist in diagnosing LD children.     

An analysis of the factor structure of the WISC-R and the effect of color on the coding subtest

The Wechsler Intelligence Scale for Children-Revised was administered to 76 subjects from 8–0 to 16–11 years. All subjects were students from rural school districts in southwest Minnesota, and were referred to a consulting school psychologist for various learning problems. The subtest scores for each subject were factor analyzed, using a principal-factor method. Three factors were found consistent with previous research, although there were mild positive loadings of all subtests except Coding on the two primary factors, suggesting that the test items measure a consistent ability such as Spearman's g. In the second aspect of the study, each subject's results on the old and new color formats of the Coding B subtest were compared. No order effects were found, and there was a highly significant difference in raw score and scaled score favoring the color format. This suggests the possibility of a color enhancement effect, at least with students having learning problems. Caution is advised for interpreting coding scores as an index of distractibility as recommended in the literature, if the subject has color-deficient vision.     

Exploring the latent structure of the Luria model for the KABC‐II at school age: Further insights from confirmatory factor analysis

The present study examined the factor structure of the Luria interpretive model for the Kaufman Assessment Battery for Children‐Second Edition (KABC‐II) with normative sample participants aged 7–18 (N = 2,025) using confirmatory factor analysis with maximum‐likelihood estimation. For the eight subtest Luria configuration, an alternative higher‐order model with Pattern Reasoning being permitted to cross‐load on the Planning and Simultaneous Processing factors provided the best fit to the normative sample data. Variance apportionment suggests that additional consideration, beyond the omnibus Mental Processing Index, of the contribution of the first‐order factor‐based scores (i.e., SQ, SM, P, and L), and in some cases the individual subtests themselves, may be warranted. Implications for clinical interpretation and the anticipated normative update of the measurement instrument are discussed.     

Predictive and construct validity of the developing cognitive abilities test: Relations with the iowa tests of basic skills

This study investigated the predictive and construct validity of the Developing Cognitive Abilities Test in a heterogeneous sample of 863 sixth grade students. Level H of the DCAT was administered during the student's sixth grade year and selected subtests of the Iowa Tests of Basic Skills were administered eight months later during their seventh grade year. Results showed that correlations between the DCAT and Iowa Tests of Basic Skills ranged from .50 (DCAT Spatial‐ITBS Language Usage) to .74 (DCAT Total‐ITBS Mathematics Problem Solving) with a median r= .635. Correlations also supported the construct (convergent) validity of the DCAT when compared to the ITBS with the DCAT Verbal subtest correlating significantly higher with the ITBS Vocabulary, Reading, and Language Usage than either the DCAT Quantitative or Spatial subtests which are not as verbally oriented. The DCAT Quantitative subtest was associated with the ITBS Mathematics Problem Solving to a greater extent than either the DCAT Verbal or Spatial subtests. © 2000 John Wiley & Sons, Inc.