Prediction of Wechsler Intelligence Scale for Children-Revised Full Scale IQ from the Quick Test of Intelligence and the Test of Nonverbal Intelligence for a referred sample of children and youth

As part of comprehensive psychoeducational assessment procedures, the Quick Test of Intelligence, Test of Nonverbal Intelligence, and the Wechsler Intelligence Scale for Children-Revised were administered to 89 children and youth, who varied in age from 6-4 to 16-10. The sample consisted of 61 males and 28 females, of whom 37 were Black and 52 White. Regression equations were computed that used the WISC-R Full Scale IQ as criteria and the TONI and QT as predictors. The results clearly indicated that the TONI and QT are equally good predictors of the WISC-R FSIQ. Implications for the clinician are discussed.     

Wechsler Adult Intelligence Scale and Wechsler Adult Intelligence Scale-Revised in a neurologically impaired population

Compared Verbal, Performance, and Full Scale IQ scores from two groups of neurologically impaired patients (N = 114) similar in age, years of education, occupation, race, sex, and etiology and location of cerebral dysfunction. One group had been given the WAIS and the other the WAIS-R. All three IQ scores were higher for the WAIS group, with Full Scale and Verbal scores significantly (p less than .05) higher. Changes in item content and standardization sample cohort effects are offered as partial possible explanation for the results. The IQ scores from the two tests cannot be considered as interchangeable for neurological patients.     

Ethnic and sex differences on the test of nonverbal intelligence, Quick Test of intelligence, and Wechsler Intelligence Scale for Children-Revised

This study investigated the performance of 89 students on the Test of Nonverbal Intelligence, Quick Test, and Wechsler Intelligence Scale for Children-Revised IQ scores for ethnic and sex differences. The sample consisted of 61 males, 28 females (37 Black, 52 White). A two-way analysis of variance and the new Duncan's Multiple Range Test were used to identify significant differences between the mean scores. The findings did not indicate any significant differences between the IQ scores with regard to ethnicity or sex. Implications of these findings are discussed in terms of assessing minority group members with the Wechsler Intelligence Scale-Revised, Test of Nonverbal Intelligence, and Quick Test.     

Multiple-group factor analysis of the Wechsler Intelligence Scale for Children

Confirmatory factor analyses were performed on the intercorrelations among the 12 tests of the WISC and WISC-R separately for age levels 7.5, 10.5, and 13.5 to test Wechsler's (1958) hypothesis that verbal and performance factors underlie these tests. At all three age levels, verbal and performance factors that accounted for approximately 50% of the total variance emerged clearly. These results provide strong empirical support for Wechsler's hypothesis.     

A comparison of Turkish and Anglo-American normative data on the Wechsler Memory Scale

This study compared the performance of 200 Turkish adults, divided by educational status and age (20-39; 40-59), with published data based upon similar-aged American and British normative samples. Results highlighted the major influence of educational background in determining performance on the WMS and the implications of this effect in interpreting normative performance.     

Comparison of the Kaufman Brief Intelligence Test and the Wechsler Intelligence Scale for Children-Third Edition in economically disadvantaged African American youth

The Kaufman Brief Intelligence Test (K-BIT; Kaufman & Kaufman, 1990) and the Wechsler Intelligence Scale for Children-Third Edition (WISC-III; Wechsler, 1991) are compared in 35 economically disadvantaged African American youth presenting for treatment in a community mental health setting. Significant correlations were found between K-BIT Composite and WISC-III Full Scale IQ scores. Results revealed significant differences between K-BIT and WISC-III scores; K-BIT Composite and Matrices mean scores were found to be 6 and 11 points higher than respective WISC-III Full Scale IQ and Performance IQ mean scores. No significant differences were obtained between K-BIT Vocabulary and WISC-III Verbal IQ scores. Our findings support the authors' recommendations for use of the Matrices subtest alone with African American youth from economically disadvantaged backgrounds (Kaufman & Kaufman, 1990).     

Administration duration for the Wechsler Adult Intelligence Scale-III and Wechsler Memory Scale-III.

The administration times for each of the subtests from the Wechsler Adult Intelligence Scale-III (WAIS-III) and Wechsler Memory Scale-III (WMS-III) were recorded for a clinical sample of 81 patients. The findings revealed that the time needed to administer the WAIS-III subtests to generate the summary scores, index scores, and both scores were 58, 51, and 65 min, respectively. The time required to complete the primary subtests on the WMS-III was 21, 15, and 6 min for Immediate Memory, General Memory, and Working Memory, respectively, resulting in a total administration time of 42 min. The time necessary to administer most of the subtests was unrelated to age, education, or performance level. These data demonstrate a shorter than expected administration time for the WAIS-III and a longer than anticipated administration for the WMS-III. Results for other clinical settings will be impacted by examiner familiarity and patient composition.     

Administration time estimates for Wechsler Intelligence Scale for Children-IV subtests, composites, and short forms

The administration times for Wechsler Intelligence Scale for Children-IV (WISC-IV) subtests, indexes, and the Full Scale IQ were recorded for 57 school children. Also determined were administration times for eight short forms and the General Ability Index (GAI). All eight short forms reduced testing time by >50%, but the GAI required approximately 56 minutes. The time to administer the 10 core subtests that yield the Full Scale IQ and index scores averaged 72 minutes (range = 42 to 100), but 31% of the administrations required 80 minutes or longer. These results indicate that administration times are quite variable and that D. Wechsler's (2003) guideline of 65 to 80 minutes can be misleading for certain settings and for specific examinees. The present research found administration time to be positively correlated with examinee age, grade placement, and Full Scale IQ. In addition, the extent of examiner experience is known to be positively related to administration speed. In the present research, as in many settings, the examiners were competent, but not highly experienced.     

Wechsler Adult Intelligence Scale-III inter-subtest scatter: a comparison of brain-damaged patients and normal controls

This study assessed the validity of Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) inter-subtest scatter (as measured by the scaled score range) as an indication of cognitive impairment due to brain dysfunction. Participants were 174 individuals with documented brain damage. Means for age, education, and WAIS-III full-scale IQ were 49.19 years (SD = 15.33), 12.57 years, (SD = 2.78), and 88.45 (SD = 17.78). The scatter ranges for brain-damaged participants were compared with those of the WAIS-III standardization sample. Results indicated that the full-scale IQ is significantly correlated with amount of scatter, r(172) = .42, p < .0001, so that a definitive answer to the question requires control of full-scale IQ. In the present analyses, inter-subtest scatter among the individuals for the sample as a whole was no greater than that for persons in the standardization sample, but subtest scatter was significantly greater for participants with IQs > or = 90. This finding suggests that there may be small differences in scatter between brain-damaged persons and normal controls, but that scatter is relatively insensitive to the presence of brain damage or dysfunction. Therefore, interpretation of marked inter-subtest variability as a sign of brain damage appears unwarranted.     

Multivariate genetic analysis of Wechsler Intelligence Scale for Children—Revised (WISC-R) factors

Wechsler Intelligence Scale for Children—Revised (WISC-R) factor scores (Verbal Comprehension, Perceptual Organization, and Freedom from Distractibility) were obtained from 574 twin pairs in the Colorado Reading Project and subjected to multivariate genetic analysis. Variances were partitioned into components common to the three WISC-R factors and to those specific to each factor. Substantial commonality, both genetic and environmental, was found among the three factors. The full model fit the data well, and estimates of heritability and environmentality indicated that about half of the phenotypic variance for each factor is due to additive genetic effects. These results were compared to those obtained in a previous twin study of the three Wechsler Adult Intelligence Scale (WAIS) factors by Tambset al. (1986).