Trait analyses of the Luria-Nebraska Intellectual Processes, Motor Functions, and Memory Scales.

Trait analyses of the Luria-Nebraska's Intellectual Processes, Motor Functions, and Memory Scales were performed using multitrait-multimethod procedures and confirmatory factor analysis. Three measures each of intellectual, motor, and memory functions were administered to 161 neuropsychiatric patients. Intellectual scales (viz., Luria-Nebraska and WAIS-R) were found to have convincing discriminant properties, but motor and memory measures demonstrated visibly less such robustness. Confirmatory factor analyses supported a three-factor model of the 9 x 9 matrix, in which each of the three Luria-Nebraska scales serves as a marker for the factors. Issues related to the neuropsychological constructs, test construction, and construct validity of measurement procedures employed in clinical neuropsychology are discussed.     

运动神经元病患者的智能,记忆及事件相关电位研究

目的：了解运动神经元病（ＭＮＤ）患者认知障碍的特点。方法：采用韦氏成人智力量表、临床记忆量表和体感刺激诱发的事件相关脑诱发电位，对１８例ＭＮＤ患者和２４例健康人进行了测验比较。结果：ＭＮＤ患者可出现不同程度的智能、记忆障碍。其中语言智商（３３．３％）、操作智商（３８．９％）、全量表智商（２７．８％）和记忆商（３８．９％）在边界以下。本组患者表现为皮质兼皮质下智能障碍的特征。其认知电位Ｐ３００的潜伏期与对照组相比明显延长（ｐ＜０．００１），波幅明显降低（ｐ＜０．００１）。     

The latent factor structure of the WAIS-R: a factor analysis of individual item responses

Factor analytic examination of a 166 x 166 intercorrelational matrix that represents individual item scores from the 11 subtests of the WAIS-R provided evidence of five interpretable factors (N = 409). Two of these were identified as the Verbal and Performance factors previously encountered in traditional WAIS-R subtest-based factor analyses. The other three factors were characterized readily as involving (1) Advanced Vocabulary skills; (2) Basic Responsivity and (3) Advanced Computational ability. All three of these "new" factors accounted for at least 10% of the total variance, and comments are made with regard to the possible significance of their discovery to such topics as subtest variation and profile psychodiagnostics, theories that pertain to the nature and structure of human intellectual functioning, and subtest-based personality measurement theories.     

Competency mandate: a model for teaching skills in the administration of the WAIS-R

The Standards for Educational and Psychological Tests as well as other official policy statements of the American Psychological Association call for competent assessment skills. However, a thorough review of the literature evidences only a handful of models that transmit these mandates into practice. The MASTERY model, a competency-based training procedure, was employed in this investigation as a cost-effective means of actualizing these professional standards. This systematic procedure brought 31 graduate students in clinical psychology to criterion level for competent administration of the WAIS-R after less than 10 hours and two administrations. Practical and research implications of this training model for clinical psychology were discussed.     

Factor analysis of the Wechsler Adult Intelligence Scale-Revised (WAIS-R) in a brain-damaged sample

The Wechsler Adult Intelligence Scale-Revised (WAIS-R) was factor analyzed for a sample of 100 diagnostically heterogeneous brain-damaged patients. Subjects were from two VA Medical Centers located in the Midwest with means for age, education, and Full Scale IQ of 52.31 (SD = 14.41), 11.37 (SD = 2.57), and 86.72 (SD = 10.78), respectively. A principal factor analysis followed by Varimax rotation provided evidence for the existence of three factors underlying the WAIS-R (i.e., Performance, Verbal, and Freedom from Distractibility). The present results are consistent with earlier studies that employed the 1939 and 1955 versions of Wechsler's Adult Intelligence Scale with neurologically impaired subjects.     

The effects of unilateral and multifocal lesions on the WAIS-R: a factor analytic study of stroke patients.

An exploratory maximum likelihood factor analysis of the inter-correlations among the 11 subtests of the WAIS-R was undertaken for 167 patients who had a primary diagnoses of cerebrovascular accident (right hemisphere, n = 79; left hemisphere, n = 55; diffuse or multifocal, n = 33). On the WAIS-R, this sample performed below normative standards (average scaled score = 7.1), but demonstrated a pattern of variability among subtests similar to the normative groups. Interestingly, VIQ-PIQ discrepancy analyses revealed V > P profiles for patients with lesions in either or both hemispheres. The best fit for the WAIS-R matrix was an oblique two-factor model comprised of the Verbal and Performance subtests. This factor solution, which was moderately correlated (.52), accounted for 58.8% of the total variance. The stability of a two-factor structure in this neurologic impaired population suggests that the WAIS-R is a robust measure, even when used within such a rehabilitation population. Only two of the eleven subtests (i.e., Comprehension and Picture Arrangement), however, were related to lesion site. Rehabilitation settings may need to rely more on neuropsychological procedures that measure the more "fluid" areas of neurocognitive ability, in contrast to the WAIS-R which appears less sensitive to the neurological impairment associated with stroke.     

Intellectual functioning and psychopathology: a canonical analysis of WAIS and MMPI relationships.

This study investigated the relationships between WAIS and MMPI scales in high pathology-average intelligence outpatients referred for psychological evaluation. No significant relationships were obtained. Apparently, no lawful relationships exist between WAIS and MMPI scales, and further investigation seems unwarranted.     

Estimated vs. empirical values of scaled-score ranges on Wechsler's Intelligence Scales: a correction

An error in the procedure that recently was presented for evaluating the abnormality of scaled-score ranges is corrected. The correction does not alter the earlier conclusion, that the procedure appears sufficiently accurate for most clinical applications.     

Prediction of verbal, performance, and full scale IQs from seven subtests of the WAIS-R

The Wechsler Adult Intelligence Scale-Revised (Wechsler, 1981) was given to 70 male VA patients, and IQs were estimated from seven subtests that require about half the administration time of the full test. Estimates correlated well with Verbal, Performance, and Full Scale IQs, and mean estimated IQs differed by less than 1 IQ point from actual means. Error sizes in predicting Full Scale IQs were small (M = 1.96) and exceeded 4 IQ points in only 3 cases. In comparison, error sizes for the Doppelt (1956) abbreviation (M = 3.71) were significantly larger and were greater than 4 IQ points in 20 cases.     

Performance profiles and cut-off scores on the Memory Assessment Scales.

The increased role of neuropsychologists in the courtroom has led to an increased effort in the detection of possible symptom exaggeration/malingering. Whereas domain specific measures of malingering have traditionally been used in this detection process, the identification of performance profiles and cut-off scores on standard neuropsychological assessment instruments may provide an alternate strategy. The present study evaluated the effectiveness of performance profiles and cut-off scores in discriminating traumatic brain injury (TBI) litigants suspected of malingering from those not suspected of malingering on the Memory Assessment Scales (MAS). Results suggest that TBI litigants suspected of poor effort will perform globally at a lower level than TBI litigants not suspected of poor effort on nearly all MAS indices, however, the performance profiles of each group was similar. Cut-off scores, especially when used in combination, were also effective in correctly classifying individuals in the two groups. The present findings warrant further research examining the utility of the proposed cut-off scores separately and concomitantly. Such research will aid the clinical neuropsychological practitioner in interpreting aberrant performance profiles on the MAS in forensic situations.     

The psychometric structure of the Wechsler Memory Scale in comparison to the WAIS-R in a low-IQ clinical population

The psychometric structure of the Wechsler Memory Scale (WMS) and its relationship to the revised Wechsler Adult Intelligence Scale (WAIS-R) were studied in an outpatient population of 103 individuals with low Full Scale IQ scores (M = 71). We found that the age correction of the WMS scores gave memory quotients (WMQ) equivalent to WAIS-R FSIQ scores, but our findings also raised problems of interpretation. If the usual rule of thumb of a 12-point discrepancy between the MQ and the FSIQ were applied, the WMS might be relatively insensitive to memory impairment in this low-IQ clinical population, in which more numerous cases of impairment could be expected. Principal components analysis of the WMS raw scores and three WAIS-R scores included as reference variables yielded five orthogonal factors: Attention/Concentration; Visual Reproductions; New Verbal Learning; Well-learned Semantic Knowledge; and Intelligence. We argue that raw scores on the WMS should be reported to optimize possible diagnostic specificity and to align the WMS with experimental and clinical research in various types of memory functioning and impairment.     

Stability of the WAIS-R and WISC-III factor structure using cross-validation of covariance structures

The stability of the Verbal Comprehension, Perceptual Organization, and Freedom from Distractibility factors of the WAIS-R and WISC-III was tested using cross-validation of covariance structure models, a methodology that employs unrestricted and restricted factor analyses. Stability was indicated if the goodness of fit of restricted models generated from unrestricted factor patterns did not degrade when applied to other age groups. If goodness of fit degraded inconsistently, the factor structure of one or both instruments was unreliable. If goodness of fit changed in some systematic fashion, an argument for true intellectual changes could be made. Results indicated consistency across age groups. Therefore, it was concluded that the three-factor structure is robust and reliable across age groups and instruments.     

Genetic Covariance Structure of Reading,Intelligence and Memory in Children

This study investigates the genetic relationship among reading performance, IQ, verbal and visuospatial working memory (WM) and short-term memory (STM) in a sample of 112, 9-year-old twin pairs and their older siblings. The relationship between reading performance and the other traits was explained by a common genetic factor for reading performance, IQ, WM and STM and a genetic factor that only influenced reading performance and verbal memory. Genetic variation explained 83% of the variation in reading performance; most of this genetic variance was explained by variation in IQ and memory performance. We hypothesize, based on these results, that children with reading problems possibly can be divided into three groups: (1) children low in IQ and with reading problems; (2) children with average IQ but a STM deficit and with reading problems; (3) children with low IQ and STM deficits; this group may experience more reading problems than the other two. Edited by Chandra Reynolds.     

The reliability of score differences on the WAIS,WISC-R,and WAIS-R

Analyzed data from the WAIS, WISC-R, and WAIS-R manuals to determine the reliabilities of the differences between Verbal and Performance IQs, of subtest comparisons, and of differences between subtest and IQ scores. The differences between the Verbal and Performance IQs were moderately reliable: 0.76 (WAIS and WISC-R) and 0.81 (WAIS-R). The means of the reliability coefficients of the differences between the 55 pairs of subtests were appreciably lower: 0.58 (WAIS), 0.62 (WISC-R), and 0.65 (WAIS-R). The most consistently reliable subtest differences were between Block Design and Vocabulary and the least reliable differences between Block Design and Object Assembly. The means of the reliability coefficients of the differences between subtest scores and the Full Scale IQs were 0.53 (WAIS), 0.58 (WISC-R), and 0.62 (WAIS-R). It was concluded that caution should be exercised when interpreting configurations on Wechsler protocols.     

Two indices of subtest scatter on Wechsler's Intelligence Scales: estimated vs. empirical values

Previous research on the scaled-score range and the number of deviant subtest scores on the WISC-R and the WPPSI has produced surprising results: Normal children exhibited much more scatter than most clinicians probably realized. Yet, in principle, these results were predictable from a knowledge of the statistical properties of scaled scores. Procedures for evaluating the abnormality of the two indices of scatter are presented and their accuracy checked against the actual distributions of the indices for the two standardization samples. The findings suggest that the procedures are sufficiently accurate for most clinical applications, which supports their use when the actual distributions of the indices are unknown.     

Differential effects on verbal-performance achievement levels on the WAIS-R as a function of progressive error rate on the Memory for Designs Test (MFD)

One hundred seventy-eight subjects participated in a study to measure the degree of selective subtest decline on the WAIS-R as a function of increased error rate on the Memory-for-Designs Test. The data show that there is an initial, significant decline in the verbal knowledge component of the verbal scale as error rate on the MFD progresses. Performance factors are only significantly related to error rate on the MFD when the latter are maximized.     

Emotional labor, strain, and performance: Testing reciprocal relationships in a longitudinal panel study

Models of emotional labor suggest that emotional labor leads to strain and affects job performance. Although the link between emotional labor, strain, and performance has been well documented in cross-sectional field studies, not much is known about the causal direction of relationships between emotional labor, strain, and performance. Goal of the present study was therefore to test the direction of effects in a two-wave longitudinal panel study using a sample of 151 trainee teachers. Longitudinal lagged effects were tested using structural equation modeling. Results revealed that the emotional labor strategy of surface acting led to increases in subsequent strain while deep acting led to increases in job performance. In contrast, there was no indication of reverse causation: Neither strain nor job performance had a significant lagged effect on subsequent surface or deep acting. Overall, results support models of emotional labor suggesting that surface and deep acting causally precede individual and organizational well-being.