WISC-R IQ Research Articles

Evaluating WISC-R change scores

Bauman (1991) evaluated the stability of WISC-R IQs in a sample of children with learning difficulties. It is argued that some of his procedures produced magnified estimates of instability. An attempted reanalysis of Bauman's data, based on information reported in his article, suggested that although stability coefficients were high, approximately 25% of the sample (as opposed to the 40% reported by Bauman) obtained significantly different IQs on second administration of the WISC-R.

Validity of the Kaufman Assessment Battery for Children when employed with children with traumatic brain injury.

The K-ABC and WISC-R were administered to 43 children with traumatic brain injury. The amount of shared variance between standard score indices of these two tests ranged from 42% to 71%, depending on which scores were considered. Correlations with degree of cerebral impairment, as measured by length of coma, were slightly higher for WISC-R IQ scores than for K-ABC global scale scores. Performance on both the K-ABC and the WISC-R was affected by the presence or absence of ocular and/or motor deficits. It is concluded that the K-ABC is not superior to the WISC-R in sensitivity to cerebral impairment and that caution is needed when one is making neuropsychological interpretations on the basis of the K-ABC.

Correlations among Special Education Students' Wisc—R IQS and Sra Scores

For 50 children in special education from rural north central Kansas school districts (30 boys, 20 girls) were recorded SRA scores (Composite, Reading, Mathematics, and Education Quotient) and WISC-R IQs (Full Scale, Verbal, and Performance). There were no sex differences on any variable and all variables intercorrelated (Pearson) significantly. The two tests gave similar results over-all, confirming that the individually administered WISC-R and the group-administered SRA provide information on children's academic abilities and, used together, give a basis for appropriate judgments regarding academic abilities.

Correlations among Wisc—R IQs and Several Measures of Receptive and Expressive Language for Children Referred for Special Education

For 42 children from rural north central Kansas school districts (27 boys, 15 girls) who were referred for Special Education testing, the WISC-R IQs (Full Scale, Verbal, and Performance), the means on the Expressive One Word Picture Vocabulary Test, the Peabody Picture Vocabulary Test--Revised, and the Test of Language Development were recorded from the children's files. No sex differences on any variable were noted; all variables correlated (Pearson) significantly but varied in magnitude. This group of tests, being intercorrelated, can be used to collect information on children's academic, speech, and language abilities. Valid judgments can be made regarding children's academic abilities for school when multiple tests are administered by professional staff.

Identifying Sources of Bias in the WISC-R

The use of intelligence tests, especially the WISC-R, has come under repeated scrutiny in recent years. Arguments for and against the use of WISC-R IQs have centered around the issue of bias. The issues of construct validity, predictive validity, and item content bias on the WISC-R were examined. Evidence regarding these biases was analyzed based on psychometric conceptions of test bias. Although this approach can lead to a narrow examination of possible bias in the WISC-R, it allows for objectivity based on empirical studies. Although all the evidence is not in, our review clearly suggests that the verdict of “not proven” is justified. Test bias has now become and will continue to be one of the major topics in psychometric research.

Relationship between Wechsler scales and Peabody Picture Vocabulary Test-Revised scores among disability applicants

Relationships, including age, race, gender, and IQ level, between the Wechsler intelligence scales (WISC-R, WAIS-R) and the Peabody Picture Vocabulary Test-Revised (PPVT-R) were studied among 206 applicants for disability benefits in a private practice setting. We found that the PPVT-R seriously underestimated WISC-R IQs by an average of 5 points and WAIS-R IQs by an average of 12 points. Results were discussed in terms of psychometric findings and clinical application. The study demonstrates that psychologists in private practice settings can use the product of their daily work to address important questions that require empirical answers, which, in turn, can influence clinical practice.

A follow-up comparison of WISC-R and WAIS-R IQs in a residential mentally retarded population

This study corroborates earlier findings that the WISC-R and WAIS-R cannot be regarded as equivalent testing instruments. Replication of the authors' previous data showing that the WAIS-R yields consistently higher scores for intellectually subaverage subjects provides further evidence that this testing artifact must be taken into account in interpreting differences in scores on the two tests.

Measuring stability and change in WISC-R IQS

Measuring stability and change in WISC-R IQS

Ib interneuron activity in human muscle tone disorders

In this paper we explore the prevalence of ictal and interictal epileptiform discharges (IEDs) and sleep disorders in ADHD children referred to a sleep clinic for all night video-PSG. Forty-two ADHD outpatients (35 males and 7 females) underwent video-PSG and a behavioural/neuropsychological assessment. Spearman correlation coefficients (p < 0.05 criterion level) were used to assess the association between cognitive, behavioural, clinical (co-morbidity), sleep (sleep efficiency) and EEG (seizures, IEDs, localization of IEDs foci) variables. Sleep disorders were found in 86% of ADHD children; among these, 26% had RLS. 53.1% of ADHD children had IEDs (28.2% centro-temporal spikes, 12.5% frontal spikes, 9.3% temporal–occipital spikes and 2.3% generalized S–W). Nocturnal seizures were recorded in three patients: two with atypical interictal rolandic spikes and one with left frontal slow abnormalities. A significant relationship (p < 0.05) emerges between nocturnal seizures and WISC-R IQ score and visual–spatial memory test and between some cognitive variables and interictal rolandic spikes. High levels of inattention, impulsivity/hyperactivity and oppositional behaviours were related (p < 0.01 or 0.05) with Restless Leg Syndrome diagnosis. In conclusion, ADHD is a condition often associated with EEG epileptiform abnormalities. Seizures/IEDs presence seems to play a role on cognitive abilities, conversely sleep disorders have a stronger impact on behavioural rather than cognitive indicators.

Validation of the Stanford-Binet Intelligence Scale: Fourth edition with exceptional black male students

Standard Age Scores on the Stanford-Binet Intelligence Scale: Fourth Edition (SBIV) and WISC-R IQs of 51 urban black males receiving special education services were compared. Correlations between the SBIV Composite scores and WISC-R Verbal, Performance, and Full Scale IQs were 0.803, 0.826, and 0.87 respectively. Correlations between all combinations of scales ranged from 0.612 to 0.888, median r=.723. SBIV Composite mean scores did not differ significantly from the mean WISC-R Full Scale, Verbal, and Performance IQs. Regression analysis of the three subgroups (BD. LD, and EMR) indicated that the SBIV possesses differential validity for each group. Tabular comparison of precision of classification between the SBIV and the WISC-R yielded a 78% agreement. These data suggest that the SBIV possesses utility for assessing the intelligence of black students classified as BD and EMR. However, the use of the scale with LD students is unsupported.

Ethnicity and Language Dominance — Influence on the Prediction of Achievement Based on Intelligence Test Scores in Nonreferred and Referred Samples

An urban sample of referred and nonreferred Black, Hispanic, and Anglo pupils were assessed with the WISC-R and K-ABC cognitive and achievement scales. Approximately 38% of the Hispanic sample was identified as Limited-English Proficient (LEP). Analysis of various procedures revealed differences in cognitive and achievement performance due to pupils' ethnicity, referral status, and LEP status. Predictive bias was examined using Potthoff's (1966) simultaneous test of regression slopes and intercepts. For both WISC-R and K-ABC IQ measures, a number of regressions on the K-ABC Total and Arithmetic achievement measures evidenced bias across ethnic groups for both referred and nonreferred samples. Bias due to language dominance also was found for WISC-R and K-ABC composite scales. Implications of predictive bias for assessment and placement of minority and LEP children in special education classes are discussed.

WISC-R stability and re-evaluation of learning-disabled students

This study investigated the temporal stability of WISC-R IQ scores for learning-disabled subjects (N = 113). All study subjects were administered the WISC-R for an initial evaluation (M age = 8 years, 3 months) and a follow-up re-evaluation (M age = 11 years, 7 months). Pearson product-moment correlations yielded coefficients that were considerably lower than those previously reported: r = .55, p less than .001 for the Verbal IQs; r = .63, p less than .001 for the Performance IQs; and r = .58, p less than .001 for the Full Scale IQs. Results of t-test analyses indicated that only the Verbal IQ scores were significantly different when the initial evaluation (M = 89.4) was compared to the re-evaluation (M = 85.3), p less than .001. The results suggest that the WISC-R may be less stable for the learning-disabled population than for other groups and that the average 3-year test-retest time lapse was an influential factor in the reduced reliability of this instrument.

Integration of the Literature on the Intelligence of Japanese Children and Analysis of the Data from a Sequential Simultaneous Perspective

This study reviewed, integrated and interpreted the literature on Japanese intelligence that followed from Lynn's (1982) conclusion of an 11-point WISC-R IQ superiority of Japanese over American children and adolescents. Reanalyses of Lynn's data, as well as subsequent research, suggest that the supposed 11-point Japanese superiority is exaggerated. In addition, this study explored the hypothesis that Japanese children perform significantly better on simultaneous processing than on sequential processing. Regression equations derived from a sample of American children who were tested on both the WISC-R and K-ABC were applied to Lynn's data on Japanese children. Results of these analyses supported the hypothesis of a discrepancy, with Japanese Simultaneous processing being significantly greater than Sequential processing, relative to American children, across virtually the entire 6-to 16-year age range.

Relationship between lead exposure indicators and neuropsychological performance in children.

This study surveyed 237 schoolchildren in a lead-polluted industrial area in northern Italy to assess the relationship between various biological indicators (lead in blood, hair and teeth, and delta-aminolevulinic dehydratase [ALA-D] activity) and some neuropsychological functions, assessed by a battery of five psychometric tests. The geometric means of lead measured in blood, hair and teeth were 10.99 micrograms/dl, 6.79 micrograms/g and 6.05 micrograms/g, respectively. Mean ALA-D activity was 51 mU/ml RBC. By analysis of covariance, after regressing out the variance accountable to confounding variables (age, sex, occupation/education of parents), Total and Verbal WISC-R IQ and Toulouse Pieron test results were significantly affected by the levels of lead in teeth. ALA-D values also appeared to be related to WISC-R IQ results (Total, Verbal and Performance).

Early Adolescents' Performance on the WRAT Compared to their WISC-R IQs, Reading Achievement Score, and Selected Demographic Variables

The relationship between the Wide Range Achievement Test (WRAT) subtest scores and WISC-R IQs, performance on the Gates MacGinitie Reading Test (GMRT), age, grade placement, and parents' educational and occupational levels were examined for a sample of 120 middle-school students. Performance on the GMRT Vocabulary subtest accounted for a significant amount of variance in the WRAT Reading subtest scores, while the GMRT Vocabulary subtest score, subject's grade-achievement level, and the primary occupation in the family contributed significantly to the amount of variance in the WRAT Spelling subtest scores. Results of the data analyses indicated that the WRAT is an effective quick measure for classroom teachers to use with middle-school students who are experiencing learning difficulties in reading and spelling. In contrast with previous findings, WRAT subtest scores were not affected by subjects' WISC-R IQs.

An investigation of differential prediction with the WISC-R

Test bias continues to be a topic of particular concern in determining the eligibility of minority students for placement in special education programs. Although critics of IQ testing have made some concessions concerning the internal structure of IQ tests, the differential prediction of academic achievement for minority group members remains a critical issue. Investigations of the correlation between IQ tests and standardized achievement tests have typically not produced evidence supporting the differential validity hypothesis. However, critics have claimed that standardized achievement and IQ tests are alternate samples of the same behavioral domain and have called for the validation of IQ with classroom achievement. The relationship between IQ, California Achievement Test scores, and grade point average was examined for a sample of 168 (83 black and 85 white) elementary and middle school students. An examination of the correlation coefficients and regression lines demonstrated little evidence of differential prediction. A significant relation was obtained between Full Scale IQ and grade point average for both black and white students. Overall, the data suggest that the WISC-R IQ is an equally valid predictor of academic achievement for the two groups.

Hemispherectomy and diaschisis: Rapid improvement in cerebral functions after right hemispherectomy in a six year old child

Neuroradiological, neurological, and neuropsychological studies before and after hemispherectomy for seizures of a six year old boy with left hemiplegia at birth revealed striking postoperative improvement. Seizures ceased and have not recurred. Preoperative EEC studies from seven months of age revealed increasing pathological involvement of the left as well as right hemisphere. Postoperatively, normal tracings over the left hemisphere documented marked and continuing improvement. In contrast to markedly subnormal preoperative WISC-R IQs, retest at 19 months postoperatively showed WISC-R IQs within the normal range, with similar improvement in other tests of cognitive, motor and sensory functions. The arrest and reversal of the preoperative pattern of increasing deterioration and disappearance of pathological involvement of left as well as right hemisphere functions following surgery is consistent with the disappearance of diaschisis as described by von Monakow in 1914, and has conceivably significant clinical as well as theoretical implications.

Stability of WISC-R IQS: An Investigation of Ethnic Differences Over Time

This investigation examined the 3-year stability of WISC-R IQs for a balanced sample of anglo, black, and Mexican-American handicapped children. No significant differences in mean IQs were found across the three ethnic groups, although over the 3-year test-retest period, WISC-R Verbal and Performance IQs were observed to vary significantly. Specifically, Verbal IQs decreased by an average of 2 points, while Performance IQs increased by an average of nearly 3 points. It was concluded that although statistically significant, the influence of 3 years time on the intelligence test performance of this varied ethnic sample of handicapped children was clinically insignificant.

Identifying Learning Disabled Children: an Analysis of Some Measurement Problems

Research studies have reported that the WISC-R IQ's of some learning disabled children decrease during the period that the children receive individually designed education programs. It has been suggested that the apparent decreases do not necessarily reflect actual decreases in intellectual ability but rather may result from measurement problems inherent in the identification of LD children. Two models for identifying LD children were examined by applying identification criteria to a simulated population. One model employed a set of criteria which simulated standardized diagnostic measures. The second model simulated a two-stage identification process involving both teachers' clinical judgments and standardized diagnostic measures. The simulation of the two-stage process identified a sample whose characteristics closely resembled those of actual LD samples. Independently collected interview and questionnaire data obtained from school personnel involved in the LD identification process provided additional evidence that, prior to referring students for LD diagnosis, teachers screen students using idiosyncratic clinical criteria.

Comparison of WISC-R and K-ABC Regression Lines for Academic Prediction With Black and White Children

Regression lines for the prediction of group and individual achievement test scores by Wechsler Intelligence Scale for Children-Revised (WISC-R; Wechsler, 1974) Full Scale IQ and Kaufman Assessment Battery for Children (K-ABC; Kaufman & Kaufman, 1983) Mental Processing Composite were compared across race, using the Potthoff (1966) technique, for 86 black and 86 white normal students, matched on socioeconomic status, grade, school, and sex. Regression lines, using WISC-R or K-ABC IQs, did not differ significantly in predicting group achievement test scores. Significant regression line differences were found when K-ABC Mental Processing Composite, Simultaneous, and Sequential scores were used to predict K-ABC total achievement scores. No regression line differences were found when WISC-R scores predicted K-ABC achievement. Results support the use of a common regression line in the prediction of achievement scores for the two races when WISC-R Full Scale IQ and K-ABC Mental Processing Composite IQ are used t...