A comparison between the WISC and WISC-R among educable mentally retarded students

The study compared differences and similarities between WISC and WISC-R scores for 48 ten- and thirteen-year-old EMR students, who were matched according to sex and race. The WISC-R yielded significantly lower VS, PS, and FS IQ scores than the WISC for this predominantly rural Georgia population. The FS IQ scores from the WISC-R averaged 7.5 points lower than the WISC FS IQs, with similar differences noted for VS and PS scores. There was no significant difference in FS IQs between the two age groups. Results suggest that many children classified as “Borderline” or slightly above by the WISC will be classified as “Mentally Deficient” by the WISC-R.     

Comparison of the PPVT-R and WISC-R with urban educable mentally retarded students

Comparisons of the revised PPVT (PPVT-R) and the WISC-R were made with 67 EMR students. Significant differences were found between the PPVT-R mean standard scores and Verbal, Performance, and Full Scale IQs. The PPVT-R did not correlate significantly with the WISC-R scales or subtests, suggesting the tests are measuring different abilities.     

A comparison of the WISC and WISC-R

So as to compare the results of the WISC and WISC-R, both instruments were administered to 58 children randomly selected from a school population of 583. All administration and scoring was performed by the same psychologist, with a two-month interval separating the administrations for each child. All IQs were significantly higher (p <.01) on the WISC, with the Performance difference being greater than the verbal difference. Also, 8 of the 10 required subtest scaled scores were significantly greater (p <.05) on the older instrument. Regression equations were obtained to predict WISC-R IQs from WISC scores.     

A comparison of WISC-R and WAIS-R IQS in a mentally retarded residential population

Although typically regarded as equivalent instruments, the WISC-R and the WAIS-R yield significantly different Verbal, Performance, and Full Scale IQs for an intellectually subaverage group, with the WAIS-R consistently providing higher scores. Implications of this “built-in” increment for issues of eligibility for educational placements and societal benefits are serious, and careful interpretation of IQs in the context of other relevant data is necessary.     

Suitability of the California Abbreviated WISC for WISC-R subtests with mentally retarded and slow learner children

This study was undertaken to determine the suitability of the California Abbreviated WISC—Form 1 (CAW-1) for use with WISC-R subtests. Subjects were drawn from the files of previously evaluated students from two southern mountain communities. Examination of WISC records within the age and IQ ranges of the CAW-1 (CA 8-0 to 13-6, IQ 50 to 80) indicated that our sample was not significantly different from the CAW-1 noim group (N = 148, r = .85 between CAW-1 & WISC Full Scale IQ). WISC-R recods (N = 178) for the same ranges were examined and were found to be more highly predictive of Full Scale IQs (r = .91, FSIQ = .98 CAWIQ + 2.2). Extensions of the age range from 6-0 to 16-11 and of the IQ range from 40 to 100 were attempted. Final results (N = 284) indicated the CAW-1 could be used with the WISC-R over the full age range and for IQs ⩽ 100 with minor alteration (r = .96, FSIQ = 1.09 CAWIQ - 5.4). The second sample served for cross validation of these results. Using the alteration, results were consistent with original findings (N = 202, r = .93, FSIQ = .98 CAWIQ + 2.2). It was concluded that the CAW-1 was suitable for use with WISC-R subtests with minor alterations.     

Comparison of the WISC-R and PPVT for a group of mentally retarded students

This study compared the WISC-R and PPVT scores for a group of 65 students classified as mentally retarded, ranging in age from 7.5 to 14.5. Pearson product moments (r) and correlated t values were employed in the analysis of data. The evidence from the present study indicated that for this sample of mildly retarded children and youth, the PPVT IQ score is significantly higher than the Full Scale IQ from the WISC-R. The current findings indicate that the same general pattern exists for the WISC-R and PPVT as for the WISC and PPVT scores.     

A comparison of factor structures of the WISC and WISC-R

The present study compared two- and three-factor solutions for the 12 subtests of both the WISC and WISC-R for a sample of 164 black, white, and Latino children aged 7 to 15 referred to school psychologists because of concerns about their intellectual ability. The results indicated that the factor structures of the WISC and WISC-R for the same group of subjects are quite similar. They are almost identical in the factors of verbal comprehension and perceptual organization. However, a difference was noted in the third factor of freedom from distractibility.     

Matched pair comparison of WISC and WISC-R scores

Both the WISC and the WISC-R were administered to 54 children, with one half taking the WISC first and the other 27 taking the WISC-R first. Differences between mean subtest scaled scores and mean IQs were found to be influenced by the sequence of the tests, although all mean scores were higher on the second test when the WISC-R was given first. Data were presented suggesting the WISC-R given first tends to raise WISC scores, and WISC given first yields scores on the WISC-R which are essentially similar, effectively counsteracting the more “difficult” scoring for the WISC-R.     

Investigation of the WISC-R for use with retarded children: Correlation with the 1972 Stanford-Binet and comparison of WISC and WISC-R profiles

A group of 80 mentally retarded youngsters, aged 6 to 16, was tested on the WISC-R, primarily to assess the continuity of measurement between the old and new WISCs. The WISC-R IQs correlated .65 to .82 with Stanford-Binet IQ for a subsample of 45 children, resembling the coefficients between the 1949 WISC and the Binet for retarded groups. In addition, the WISC-R test profiles for the 80 children corresponded closely to the WISC test profiles for many retarded samples. Thus, there was evidence to support the continuity of the WISC-R with its predecessor for retarded populations.     

Comparability of WISC-R and WAIS IQ scores in educable mentally handicapped adolescents

The WISC-R and WAIS were administered to 30 16-year-old EMH students in a test-retest design to distribute practice effects. The average interval between administrations was approximately 37 days. Results from t-tests of significance of difference between the means were obtained for the total group and for two subgroups, one receiving the WISC-R first and one the WAIS first. Analysis of data revealed significantly higher WAIS scores on all levels of VIQ, PIQ, and FIQ for all groups.     

Sensitivity to orthographic structure in educable mentally retarded children

Thirty educable mentally retarded (EMR) children were presented an item selection task to assess their sensitivity to orthographic structure in printed English words. Analyses of performance indicated that EMR children do acquire implicit knowledge of orthographic rules and that this ability is related to the development of reading skills.     

A longitudinal comparison of the WISC and WISC-R with special education pupils

The purpose of this study was to determine the degree of comparability between the WISC and the WISC-R over time. Hypotheses were tested using a sample of 276 mildly mentally handicapped children enrolled in special education classes who had received a WISC (Trial 1) and a WISC or WISC-R (Trial 2) after an interval of approximately three years. The sample was grouped on the basis of test administered in Trial 2. Group I contained those children who received the WISC on Trial 2 and included 183 children, of whom 121 were males and 62 were females. Mean age at time of initial testing was 8–10; mean age at second testing was 11–8. Group II was composed of 93 children who had been posttested on the WISC-R and included 72 males and 21 females. Mean age at initial testing was 9–5; mean age at posttest was 13–0. The study was conducted in five school districts and one county department of education. Verbal IQ, Performance IQ, and Full Scale IQ for both instruments administered were transcribed from the special education folders of the children. The design used to test hypotheses was repeated measures analysis of variance. Data analysis resulted in rejection of the hypotheses that the WISC-R yields mean Verbal, Performance, and Full Scale IQ scores greater than or equal to the corresponding mean IQ scores of the WISC. It was concluded that the WISC-R may unfairly penalize special education children who are reevaluated with this instrument. Fluctuations in IQ scores due to the instrument of measurement must be recognized, and appropriate action should be taken to insure that children are evaluated for special class placement on comparable bases.