A comparison of the Slosson intelligence test and the WISC-R with elementary school children

The WISC-R and the Slosson Intelligence Test (SIT) were given to 69 randomly selected children in grades one through six in an urban school system. A regression equation for predicting WISC-R full scale IQ from SIT was developed. Previous studies had reported that SIT IQs tended to be consistently higher than WISC-R IQs. The present study revealed that SIT IQs were considerably higher than WISC-R IQs in the upper range and slightly lower in the lower range. A possible reason for the discrepancy is that the present study used a normal population and previous studies used restricted ranges. It was concluded that the SIT provides a good estimate of WISC-R full scale IQs when a regression equation is used. It was recommended, however, that educational placement decisions should not be made on the basis of any single IQ measure.     

Comparability of the WISC and the WISC-R in normal children of divergent socioeconomic backgrounds

WISC and WISC-R IQs of two groups of normal ten-year-old children from divergent socioeconomic backgrounds (N = 36) were compared in a counterbalanced research design. Generally, all WISC mean IQs were higher than the WISC-R mean IQs for both groups of children. Significantly higher WISC IQs were obtained on the Verbal and Full Scales of the low socioeconomic group and on the Performance and Full Scales of the high socioeconomic group. Correlations between tests for Verbal, Performance, and Full Scale IQs were.95,.79, and.91 for the low socioeconomic group, and.84,.57, and.87 for the high socioeconomic group. Although practice effects did not appear to significantly affect IQs of the low socioeconomic group, various practice effects were observed in the high socioeconomic group. Negative effects were observed for both WISC and WISC-R on the Verbal Scale, whereas positive effects were observed on both Performance and Full Scales in this group. Analysis of simple effects reveals that WISC and WISC-R IQs did not differ significantly upon first administration, but were significantly different upon second administration. Conclusions were drawn that while WISC-R yields a lower IQ estimate than WISC for children of lower ability, results were not so clear for the children of higher ability, due to practice effects which disproportionately favor increases on WISC IQs upon second administration. The greater practice effects found on the WISC have implications for comparisons of the two tests in counterbalanced research designs. Simple randomized or treatment-by-levels design may be more useful in comparisons of the WISC and the WISC-R because of the bias introduced by counterbalanced designs.     

A longitudinal comparison of the WISC-R and WAIS-R

The degree of comparability between the WISC-R and WAIS-R over time was assessed for two samples of referred adolescents of borderline intelligence intially administered a WISC-R and retested on the WAIS-R after three years. Results indicated that the WAIS-R significantly overestimated the WISC-R IQs by 3 to 5 points. Differences were most marked at the lower ability levels; as IQs aproached average, scores were increasingly comparable.     

Comparison of the slosson intelligence test,revised norms,and WISC-R for children with learning problems and for gifted children

The Slosson Intelligence Test (revised norms) (SIT) and the WISC-R were compared in two samples of children. In the first sample, there were 34 black and 27 white rural Southeastern Alabama children being considered for special education classes. In the second sample, there were 4 black and 81 white suburban Alabama children being considered for classes for the talented and gifted. In both samples, correlations between the SIT IQ and WISC-R Full Scale IQ were significant (rs of .70 and .48, respectively). However, in the special education sample, SIT IQs were significantly higher than WISC-R Full Scale IQs by about 7 points. The results from both samples provide a moderate degree of support for the concurrent validity of the revised SIT norms, using the WISC-R as the criterion. However, the IQs on the two tests may not be interchangeable.     

A longitudinal study of the Stanford-Binet and WISC-R with special education students

A group of 95 black and 52 white low socioeconimic children assigned to special education calsses were initially given the Stanford-Binet (1972 norms) and three years later the WISC-R. Correlations between the Stanford-Binet and WISC-R Full Scale IQs were significant in both ethnic groups, with r=.60 for the total group. Correlations between the Stanford-Binet and WISC-R subtests also were generally signiificant (rs between .29 and .52 for the total group). Stanford-Binet and WISC-R Full Scale IQs did not differ significantly. For this sample of special education children, the Stanford-Binet was found to have satisfactory predictive validity.     

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.     

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.     

WISC,WISC-R,S-B L&M,WRAT: Relationships and trends among children ages six to ten referred for psychological evaluation

Thirty children ages 6-10 were selected who had been referred for psychological evaluation from the public schools. WISC-R was significantly lower than WISC FS IQs and similar to S-B L&M IQs (1972). Each scale predicts reading, spelling, and achievement in a significant manner. The use of the WISC-R over the WISC will rosult in greater numbers of children being classified as retarded.     

Comparison of SIT and WISC-R IQs among special education candidates

The validity of the SIT was investiagated with 50 public school children in Grades 1 through 4; the WISC-R served as the congruent validating criterion. The SIT correlated significantly with the WISC-R and overestimated the WISC-R IQs. Statistical data for sexual and racial stratifications were also given.     

The WISC-R as a predictor of achievement

This study investigated the validity of the WISC-R IQs as predictors of achievement as measured by the PIAT. Both tests were administered to 188 children referred to the author because of learning problems. Regression analyses were run with each of the PIAT subtests and the total score as criteria and the WISC-R IQs as predictors. Each of the IQs was a significant predictor of each of the PIAT subtests, but the Verbal IQ predicted best. Regression equations were provided and several indications of the importance of the results were presented.     

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.     

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.     

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 WISC-R IQS and factor scores in predicting achievement for Mexican-American children

The predictive validity of the WISC-R IQs and factor scores was examined with a sample of 64 Mexican-American children. All the correlations among the WISC-R factor scores and academic achievement as measured by the Wide Range Achievement Test (WRAT) were found to be low, ranging from .09 to .31. Significant relationships were observed only between WRAT Reading and Perceptual Organization (PO) factor, WRAT Arithmetic and PO factor, and Freedom from Distractibility (FD) factor and WRAT Arithmetic scores. In contrast to this, however, significant relationships were observed between IQ scores and achievement measures, suggesting predictive utility of the WISC-R IQs in predicting achievement for Mexican-American children.     

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.     

Relationship between PPVT and WISC-R in children with reading disabilities

The Peabody Picture Vocabulary Test (PPVT), Form A was compared to the Wechsler Intelligence Scale for Children-Revised (WISC-R) in two samples of children with reading disabilities. One group of 14 children, referred to a university clinic, were administered the WISC-R, followed by the PPVT. The second group of 38 children from a private learning disability center were administered the PPVT first, followed by the WISC-R. In the combined sample, the PPVT IQ (X̄ = 109.2) was significantly higher than the WISC-R Verbal IQ (X̄ = 98.9), Performance IQ (X̄ = 97.0), and Full Scale IQ (X̄ = 97.5). Similarly, the PPVT IQ was significantly higher than the WISC-R Full Scale in both samples separately, regardless of which test was administered first. In one case, the PPVT IQ was 50 points higher than the WISC-R IQ. Correlations between the PPVT and WISC-R Verbal, Performance, and Full Scale IQs were significant (rs = .56, .29, and .50, respectively). The results suggest that the two tests do not provide interchangeable IQs for a population of reading disabled children.     

A comparison of three screening tests and the WISC-R in special education evaluations

Eighty public school children referred for psychological assessment for potential special education placement were given the Slosson Intelligence Test, Peabody Picture Vocabulary Test, Developmental Test of Visual-Motor Integration, and Wechsler Intelligence Scale for Children—Revised. Correlational and regression techniques were used to determine the effectiveness of the three former measures in predicting WISC-R IQ scores. SIT IQs were found to be the best predictors of WISC-R Verbal, Performance, and Full Scale IQs; however, these statistical relationships reveal little about the clinical utility of the screening measures. Problems with use of the current findings and those of other studies are discussed.     

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.     

The concurrent validity of the Cognitive Levels Test with the Wechsler Intelligence Scale for Children-Revised for a sample of referred children and youth

The present investigation compared the Cognitive Levels Test (CLT) and the Wechsler Intelligence Scale for Children-Revised (WISC-R) scores for 55 children who were referred for remedial educational services. A comparison of the correlations for each of the criterion measures from the WISC-R showed a consistent significant positive relationship with the CLT. A repeated measures analysis of variance that compared standard scores for the CLT with those of the WISC-R indicated that significant differences existed between WISC-R IQs and the CLT Cognitive Index. Implications concerning the validity of the Cognitive Levels Test are discussed.     

Further investigation of comparability of the WISC-R and PPVT-R for children and youth referred for psychological services

Comparisons of the WISC-R and PPVT-R were made with 37 students (25 boys, 12 girls). Pearson product moments (r) and two-tail f-tests were employed in the data analysis. The sample ranged in age from 6-2 to 14-6, with a mean age of 10-1, and SD=2.6. There were no significant differences between the WISC-R IQs and PPVT-R standard scores. The PPVT-R did not correlate significantly with the WISC-R IQ scales.