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.     

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.     

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.     

Vision and academic performance of learning disabled children

The purpose of this study was to assess difference in academic performance among myopic, hyperopic, and emmetropic children who were learning disabled. More specifically, myopic children were expected to perform better on mathematical and spatial tasks than would hyperopic ones and that hyperopic and emmetropic children would perform better on verbal measures than would myopic ones. For 439 learning disabled students visual anomalies were determined via a Generated Retinal Reflex Image Screening System. Test data were obtained from school files. Partial support for the hypothesis was obtained. Myopic learning disabled children outperformed hyperopic and emmetropic children on the Key Math test. Myopic children scored better than hyperopic children on the WRAT Reading subtest and on the Durrell Analysis of Reading Difficulty Oral Reading Comprehension, Oral Rate, Flashword, and Spelling subtests, and on the Key Math Measurement and Total Scores. Severity of refractive error significantly affected the Wechsler Intelligence Scale for Children--Revised Full Scale, Performance Scale, Verbal Scale, and Digit Span scores but did not affect any academic test scores. Several other findings were also reported. Those with nonametropic problems scored higher than those without problems on the Key Math Time subtest. Implications supportive of the theories of Benbow and Benbow and Geschwind and Behan were stated.     

Comparison of PPVT-R and WISC-R in a mild/moderate handicapped sample

The Peabody Picture Vocabulary Test-Revised, Form L was compared with the Wechsler Intelligence Scale for Children--Revised with a sample of 32 mild/moderate handicapped students (24 boys, 8 girls). Significant correlations were found between the WISC-R Full Scale IQ (.46) and the WISC-R Verbal IQ (.50) and the PPVT-R, but no significant correlation was found between the WISC-R Performance IQ and the PPVT-R (.34). Mean scores on the PPVT-R and WISC-R were significantly different.     

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 between intelligence and vocabulary

This study explored the correlations of scores on the Wechsler Intelligence Scale for Children-III in screening language problems and scores on the three Comprehensive Receptive and Expressive Vocabulary Test subscales. Participants were 243 students ages 6 to 17 years in Grades K-11 who were identified as learning disabled, learning disabled with speech impairment, mentally retarded, and speech impaired. Analysis indicated strong correlations between the two measures, particularly between the CREVT General Vocabulary and WISC-III Verbal IQ (r = .80), WISC-III Verbal Comprehension Index (r =.83), and the Vocabulary subtest (r =.76). These results held across the grades. Supporting earlier studies of relationships of Verbal IQ and Receptive Vocabulary, correlations were lower between participants in Grades K through 2 than those in higher grades on the WISC-III Verbal IQ and the Receptive Vocabulary subtest. An analysis of the accuracy of the WISC-III for classifying students with language problems indicated improvement in classification over chance. These findings suggest that the WISC-III may be an effective screen for language problems.     

Relationship between WAIS-R and wide range achievement test in a sample of mixed patients

Correlations between the WAIS-R Verbal, Performance, and Full Scale IQs, WAIS-R subtest scaled scores, and Wide Range Achievement Test Reading, Spelling, and Arithmetic standard scores were computed for a sample of 60 patients at a V.A. medical center who were referred for routine psychological evaluation. The Full Scale IQ and Verbal IQ yielded large correlations with the three achievement area standard scores (rs of .60 to .76). However, Performance IQs correlated moderately with reading and spelling scores (rs of .41 and .42), but a larger correlation obtained with arithmetic scores (r = .66). The results support the concurrent validity of the WAIS-R.     

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.     

Differential effect of lesion side on intra-individual variability in children with focal lateralized epilepsy

A differential impact of hemispheric side (left vs right) on cognitive measures, specifically Verbal and Performance IQ, has been described previously for both focal onset seizures and lateralized brain lesions. This study revealed a differential effect on intra-individual variability, measured as subtest scaled-score range, on the Dutch WISC-R and WISC-III, in children with epilepsy. The presence of documented brain lesion was associated with elevated variability on the Verbal Scale for the left hemisphere seizure group and with decreased variability on the Verbal and Full Scales for the right hemisphere seizure group.     

Variations in WISC-R patterns of learning disabled children

The WISC-R was administered to 19 learning disabled students at the time of diagnosis and following a period of time in special program placements. Group analyses indicated fluctuations between testing times in the Verbal and Full-Scale IQs and the V-P IQ discrepancies. Small but significant differences in Verbal, Performance and V-P scatter indices were observed at one or both testings in comparison to the normal standardization sample. Although the suggested group pattern for learning disabled children based on the Bannatyne categories was confirmed on both occasions, there was considerable variation for individual subjects.     

Correlations among GPA and scores on the Spanish version of WISC-R and the Woodcock-Johnson Achievement subtests for 10- to 12-year-old Puerto Rican children

The purpose of this study was to explore the correlations among GPA, the Spanish version of the WISC-R, and the Woodcock Johnson Achievement subtests for a group of Puerto Rican children. The tests were administered to a sample of 32 children between the ages of 10 to 12 yr. in Grade 4. Pearson correlations between the Verbal, Performance, and Full Scale scaled scores in the WISC-R (Spanish Edition) ranged between .37 to .83. Correlations between subtests of the Woodcock-Johnson Achievement Test ranged from .26 to .70. The moderate correlation between the Total scaled scores on the Woodcock-Johnson and the scaled scores of the Performance, Verbal, and Full Scales of the Spanish WISC-R is indicative of the value of these Spanish-language instruments in diagnosing the intellectual and academic performance of Spanish-speaking populations in the United States.     

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.     

Wechsler Digit Span subtest: diagnostic usefulness with dyslexic children

The current study supports Levinson's contention (1988) that the diagnosis of dyslexia cannot be based solely on neurophysiological evidence but must be made in conjunction with reading and educational test scores. Contrary to much current research, in the present study specific WISC-R profiles are identified within a stringently defined subgroup of 57 9- to 12-yr-old dyslexic children. Well-defined subtest scatter can differentiate dyslexics from proficient readers. In particular, the Digit Span subtest, which is not routinely administered by psychologists or included in computing Verbal IQ, can be considered an important component of a diagnostic battery. Unexpectedly, Coding emerged with Digit Span as a third factor in a principal component analysis; statistically significant sex differences appeared on the Coding task. Findings appear to confirm the phonological encoding deficiencies displayed by dyslexics on the Digit Span subtest. This study strongly supports consideration of WISC-R subtest differences, along with correlated factors, neurophysiological and perceptual evidence, when diagnosing dyslexic children. Cross-validation is planned.     

Comparison of the WISC-R and Woodcock-Johnson tests of cognitive ability

The relationship between the Woodcock-Johnson Tests of Cognitive Ability (WJTCA) and Wechsler Intelligence Scale For Children-Revised (WISC-R) was investigated in a referral sample of 52 elementary aged students. The WJTCA and WISC-R provided comparable ability estimates as reflected by a .74 correlation between the respective Full Scale scores and no significant (.05 level) mean difference (WJTCA Broad Cognitive Ability mean = 97.1, WISC-R Full Scale mean = 96.8). The comparability of the WJTCA/WISC-R global ability estimates is contrary to lower WJTCA scores found in recent studies with learning disabled students, with the current findings supporting the criticism of those studies as advanced by the author of the WJTCA.     

Neuropsychological assessment of learning disabilities: a discriminant analysis

The neuropsychological test scores of 23 learning disabled children were compared with those of a matched population of normal children in the 9-1 to 13-1 age range. All children were administered the Wechsler Intelligence Scale for Children-Revised (WISC-R), a dichotic listening task involving both free and directed recall conditions, a handedness inventory, the Tactile Performance Test and the Category Test from the Halstead-Reitan Neuropsychological Test Battery. A multivariate analysis of variance resulted in a significant separation between groups (p less than .001) using these procedures. A stepwise discriminant function analysis revealed that both of the directed dichotic tasks contributed the most of all 13 measures to the significant group separation. In addition, other cognitive tasks found to discriminate normal from learning disabled children include general verbal processes, concept formation, and tactile memory. These findings suggest that the directed dichotic listening procedure and the WISC-R Verbal IQ measure are reasonably valuable clinical tools in the classification of learning disabilities.     

Factor analysis of responses to the WISC-R for gifted children

Several researchers have focused on the question of whether the traditional two-factor interpretation of WISC--R scores proposed by Wechsler (1974) is appropriate in selecting students to be admitted to gifted programs. Some researchers have suggested that the two-factor solution (Verbal and Performance) of Karnes and K. E. Brown provides the appropriate model, while others have proposed an alternative model based on exploratory research with gifted and average students. The current study expands exploratory findings of S. W. Brown with Rood in 1982 and Yakimowski in 1987, using confirmatory factor analytical procedures. The confirmatory factor analyses for selected groups of gifted (n = 158) and average (n = 195) students (M = 9.6 yr.) indicate that the alternative three-factor solution model may be a better system for interpreting the pattern of WISC--R subtest scores of gifted students than the conventional Verbal and Performance solution.     

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.     

Factor analysis of the wisc-r and the wrat with a referral population

Scores on the WISC-R and the WRAT from a referral sample of 250 children, ages 6 through 11, were factor analyzed using a principal factor method with varimax rotation. Results offered support for interpretation of WISC-R scores in terms of Verbal and Performance scales, and for interpretation of WRAT scores as a separate achievement factor. The contention that achievement and intelligence tests measure identical constructs is challenged.     

Validity of the Woodcock-Johnson tests of cognitive ability: A comparison with the WISC-R in LD and normal elementary students

The study addresses the external validity of the Woodcock-Johnson Tests of Cognitive Ability (WJTCA) in learning disabled (LD) elementary school children by controlling for two methodological errors Woodcock identified in previous studies: (a) Intellectual ability range was restricted for both normal and LD samples to counteract an artificial inflation of mean WISC-R scores without concomitant effect on WJTCA scores, and (b) the WISC-R was readministered during data collection. In addition, normals were used as controls for LD students. WJTCA scores were correlated and compared with WISC-R scores and reading achievement test scores in 20 normal, 20 mild-to-moderate LD, and 20 severe LD third-, fourth-, and fifth-grade students. Results indicate comparability of mean WISC-R and WJTCA Full Scale scores in the normal sample, but manifest a significantly lower WJTCA Full Scale scores in the LD samples, despite a strong degree of correlation between the two tests in each sample. The significant linear trend of increasing mean WISC-R/WJTCA discrepancy across the severity of LD strongly suggests that the lower WJTCA scores in the LD samples is a function of the instrument's achievement emphasis and refutes the possibility of systematic error in the WJTCA norms. Results suggest that the WJTCA's achievement emphasis jeopardizes its validity for assessing and classifying LD students within the currently accepted and mandated ability-achievement discrepancy model of specific learning disabilities.