Adolescents earlier diagnosed as dyslexic show major IQ declines on the WISC-III

Adolescents (n=43) previously diagnosed as dyslexic/reading disabled had markedly lower IQ scores on the newly standardized Wechsler Intelligence Scale for Children (WISC-III) than on the earlier administered WISC-R. The declines for Verbal, Performance, and Full Scale IQs were 10, 12, and 11 points, respectively, which were twice as great as in a subset of the standardization sample given both versions of the WISC. The adolescents did not show a significant decline in standard scores from the Wide Range Achievement Test (Level I to Level II). However, only two subjects had current reading and spelling standard scores above the 25th percentile. The impact of lower WISC-III IQs on guidelines for classification of students as learning disabled is discussed.     

WIAT subtest and composite predicted-achievement values based on WISC-III verbal and performance IQs

Critical values tables for determining significant differences between Wechsler IQs and WIAT subtests and composites based on a predicted-achievement method are provided in the WIAT manual for the Full Scale IQ and have been constructed recently for Verbal and Performance IQs (Flanagan & Alfonso, 1993). In order to use these tables, however, a predicted achievement score(s) is required. The process of calculating predicted-achievement scores is time-consuming and may result in errors, especially when more than one ability-achievement comparison is warranted. The present paper provides tables of WIAT subtest and composite predicted-achievement standard scores based on WISC-III Verbal and Performance IQs. These tables allow examiners to determine quickly ability-achievement discrepancies based on WISC-III Verbal or Performance IQs when they are used in conjunction with the critical values tables provided in our earlier article. These tables are most useful for the accurate assessment and diagnosis of learning disabilities.     

The relationship between the Woodcock-Johnson psycho-educational battery-revised (early development) and the Wechsler preschool and primary scale of intelligence-revised

The concurrent validity between the Woodcock-Johnson Psycho-Educational Battery-Revised Tests of Cognitive Ability (WJ-R, COG) (Early Development) and the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R) was examined. These two measures were administered in two separate sessions in counterbalanced order to 30 normal 3-, 4-, and 5-year-old subjects from the Midwest. Findings suggested that the WJ-R Broad Cognitive Ability (BCA) and the WPPSI-R Full Scale IQ (FSIQ) and Verbal IQ (VIQ) were significantly correlated, but that the mean BCA scores on the WJ-R (COG) were significantly below the mean FSIQ scores on the WPPSI-R by only - 4.50 standard score points. No age or sex differences were found on either the WJ-R (COG) or the WPPSI-R. Significant correlations were found between the WJ-R (COG) BCA and the following WJ-R (COG) Broad Ability Factor scores: Long-Term Retrieval, Short-Term Memory, Auditory Processing, and one test called Picture Vocabulary representing comprehension-knowledge. A significant correlation was also found between the WPPSI-R Performance IQ (PIQ) and the WJ-R (COG) Visual Processing cluster. Findings are discussed in terms of the theories of intelligence underlying each test. Implications for assessment of preschoolers under PL 99–457 also are discussed.     

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.     

The relationship between the Wechsler Intelligence Scale for Children-Revised and the Wechsler Intelligence Scale for Children-III scales and subtests with gifted children

Each year thousands of children are evaluated or reevaluated utilizing the current edition of the Wechsler Intelligence Scale to determine their eligibility for gifted programs. The Wechsler Intelligence Scale for Children-III (1991) is new enough that only limited research is available on how it compares to the previously used Wechsler Intelligence Scale for Children-Revised (1974). The purpose of this study was to determine the comparability between the previously dominant intelligence scale, the WISC-R, and the revised WISC-III with gifted children. The results of this study indicate that the latest revision (WISC-III) and the earlier version (WISC-R) produce remarkably similar scale and subtest scores when administered under clinical conditions to gifted children. All 51 children determined eligible through the administration of one of these two Wechsler tests would have been eligible for services had the other test been administered. The Verbal and Performance scale IQ scores were within two points of each other across the two test administrations, while only a one-point difference existed between the Full Scale IQ scores. The Arithmetic, Comprehension, and Object Assembly subtest scores were in high agreement across the two administrations (p<.01). The level of agreement between some subtests across the two administrations suggests that clinical judgment is just as important as scores in considering who is eligible for gifted programs.     

Screening for giftedness with the Slosson and the scale for rating behavioral characteristics of superior students

Children who had been nominated as potential candidates for gifted programs were assessed to determine the relationships among certain behavioral and intellectual characteristics. Records were compiled listing 132 first- through eighth-grade children's race, sex, age, grade level, Slosson Intelligence Test (SIT) IQ scores, Scale for Rating Behavioral Characteristics of Superior Students (SRBCSS) scores, and WISC-R IQs. Only children achieving SIT IQs of 130 or higher were included. A regression equation for the prediction of a WISC-R Full Scale IQ score from a given SIT score was computed and compared to that developed for predicting the WISC-R IQ in another study. All variables except SIT IQ were poor predictors of WISC-R IQ scores. A moderate correlation was computed between SIT and WISC-R Verbal and Full Scale IQ scores. A somewhat lower, but still significant, degree of relationship was found between SIT and WISC-R Performance IQ scores. Some difficulties with using the SIT as a screen for gifted programs are discussed.     

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.     

A comparison of WISC and WISC-R results of urban educable mentally retarded students

Twenty urban EMR students' WISC-R scores were compared with their previously administered WISC scores. The average interval between administrations was approximately three years. Significant coefficients of correlation were obtained between five corresponding subtests and between Performance IQs and Full Scale IQs. Results from t tests for correlated data indicated that mean WISC-R Verbal, Performance, and Full Scale IQ scores were not significantly lower than their corresponding WISC scores. The results of this study indicated that WISC-R scores in comparison to WISC scores appeared to be more stable in the lower IQ ranges and less vulnerable to cultural bias.     

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.     

Concurrent validity of the test of nonverbal intelligence with learning disabled children

Results of the TONI, WISC-R, and WRAT were compared for a sample of 66 learning disabled children: 51 males (32 white, 19 black) and 15 females (9 white, 6 black) whose mean age was 9–5 (SD = 1–10). The mean score of the TONI was significantly different from the Performance IQ. Nonsignificant differences were found between the TONI and Full Scale IQ and between the TONI and Verbal IQ. Correlation coefficients between the TONI and WISC-R ranged from a low of .35 for the Verbal IQ to .44 for both the Full Scale and Performance IQs. The correlation coefficients between the TONI and standard scores of the WRAT were .38, .27, and .23, for Reading, Spelling, and Arithmetic, respectively. Implications of these findings are discussed.     

Accounting for Native/non‐Native differences in IQ scores

Verbal and Performance WISC‐R subscale scores were collected from 691 Native and 234 non‐Native children in Grades 2 and 4. Samples were drawn from each of four sites in North America: Northern Woodlands, Plains, Northwest coast, and Southwest Desert. Native children had substantially lower IQ scores than non‐Native, the difference especially pronounced for the Verbal subscale. Biopsychosocial variables including maternal and child health, socioeconomic status, parental attitudes toward school and toward cultural separation, and children's English‐language skills accounted for 67% of the Native/non‐Native difference on the Performance subscale and 57% of the Verbal subscale score difference. Implications for understanding Native/non‐Native IQ score differences and for interventions to promote Native children's academic success are discussed. © 2000 John Wiley & Sons, Inc.     

College student performance on the general ability measure for adults and the wechsler intelligence scale for adults‐third edition

This study examined the concurrent validity of the General Ability Measure for Adults (GAMA¹; Naglieri & Bardos, 1997) and the Wechsler Adult Intelligence Scale‐Third Edition (WAIS‐III; Wechsler, 1997). Sixty college students were administered both instruments in counterbalanced order. A comparison of the mean scores on the GAMA and WAIS‐III indicated that the sample obtained similar GAMA and WAIS‐III PIQ scores. In contrast, the sample's mean GAMA IQ score was significantly lower than the sample's mean FSIQ and VIQ scores. Although the GAMA IQ score was positively correlated with all WAIS‐III IQ and Index scores, this new instrument was more clearly associated with visual‐spatial reasoning, as defined by the WAIS‐III PIQ. The GAMA's accuracy in predicting performance on the WAIS‐III FSIQ and PIQ also was examined, with the GAMA underestimating WAIS‐III FSIQ and PIQ scores for participants falling within the Superior and Very Superior range of intellectual functioning. © 2001 John Wiley & Sons, Inc.     

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.     

Clinically and theoretically derived WISC-R subtest regroupings: Predicting academic achievement in a referral population

Attention continues to be directed toward the WISC-R as a tool for understanding children's learning problems. The formulation of WISC-R subtest regroupings (apart from the traditional Verbal, Performance, and Full Scale IQs, and the empirically derived factor scores) may provide a basis for score interpretation and the generation of hypotheses regarding children's cognitive strengths and weaknesses. The present investigation analyzed the predicitive utility of several WISC-R subtest recategorizations with regard to academic to achievement as measured by the WRAT. The sample consisted of 105 children who had been referred for psychoeducational evaluation because of classroom learning problems. Stepwise regression analyses indicated that many of the regroupings were significant predictors of academic achievement. Generated regression equations are presented.     

Comparison of bilingual children on the WISC-R and the Escala de Inteligencia Wechsler Para Ninos

A comparison was made of bilingual Puerto Rican students' scores on the WISC-R and the Escala de Inteligencia Wechsler Para Ninos to see whether there were any differences in scores based on the language in which they were tested. These children were determined to be equally proficient in English and Spanish, based on scores from the Dailey Language Facility Test. There were no significant differences between the Full Scale and the Verbal Scale scores on both tests, but significant differences were found between the Verbal and Performance Scale scores on both tests. Caution in testing bilingual children before determination of bilinguality, as well as further research into development of intelligence tests for individual culture groups, is recommended.     

A comparison of three different measures of intelligence with preschool children identified at-risk

This study compares three different measures of intelligence used with preschool children identified “at-risk.” Seventy preschoolers were administered the Wechsler Preschool and Primary Scale of Intelligence, Peabody Picture Vocabulary Test-Revised, and the Expressive One-Word Picture Vocabulary Test. The sample consisted of 21 girls and 49 boys, of which there were 30% Orientals, 3% White, 20% Black, and 7% Native Americans. Pearson's product-moment correlation was used to analyze the data. Correlated t-tests were used to calculate the differences between the mean IQs for the tests. The PPVT-R and EOWPVT were found to be significantly correlated with the Verbal and Full Scale IQ scores of the WPPSI. In addition, the PPVT-R and EOWPVT correlated significantly with the Performance Scale IQ of the WPPSI. The results and their implication for the assessment of preschool children are discussed.     

The long-term stability of WISC-R scores in mildly retarded and learning-disabled children

This study addresses the need for systematic longitudinal research documenting the stability of WISC-R scores in special education populations. WISC-R scores of 100 learning-disabled and 60 mildly retarded children retested on three separate occasions at three-year intervals were examined. The stability of WISC-R scores was evaluated according to three different criteria: (a) the consistency of group means over time, (b) the frequency of significant changes in individual scores, and (c) correlations between administrations as an index of stability of subjects' relative positions in the group. Different results were obtained depending on the criterion considered. Examination of group means and correlation coefficients indicated that Full Scale IQ was fairly stable over a period of six years for both learning-disabled and mildly retarded samples. However, greater variability was noted when examining the frequency of changes in individual subject's scores. Verbal IQ and Performance IQ demonstrated somewhat more variability by all criteria examined. The implications of these results with regard to the importance assigned to IQ in special education classification decisions, the usefulness of retesting IQ in three-year reevaluations, and the efficacy of special education are discussed.     

Predictive validity of the Slosson Intelligence Test with the WISC-R and the WRAT-R level 1

Slosson Intelligence Tests (SITS) administered by school guidance counselors correlated significantly with school psychologist administered WISC-Rs (r=.75). The Slosson IQ correlated significantly higher with the WISC-R Verbal IQ than with the Performance IQ score. The mean Slosson IQ was a statistically significant 4.4 points higher than the mean WISC-R Full Scale IQ (p<.01).     

The effect of familiarity with the examiner on WISC-r verbal,performance, and full scale scores

The Wechsler Intelligence Scale for Children-Revised (WISC-R) was administered to 72 elementary school children (36 first graders and 36 fifth graders). Three methods of pretest rapport establishment were compared for each of two age groups. Treatment Group 1 received less than 5 minutes of pretest rapport establishment immediately preceding testing. Treatment Group 2 received 15 minutes of rapport establishment immediately preceding testing. Treatment Group 3 received 5 minutes of rapport establishment on two of the five school days prior to testing and 5 minutes immediately preceding testing. It was found that time spent in establishment of familiarity with the examiner as determined by the three treatment conditions had no significant effect on WISC-R Verbal, Performance, or Full Scale scores for this sample. Also, no significant difference was found between 6-year-old and 10-year-old students under the various treatment conditions. Finally, no significant differences on WISC-R Verbal, Performance, or Full Scale scores were found as a result of the interaction of age and familiarity conditions.     

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.