Test-retest reliability and practice effects of the Wechsler Memory Scale-III

Although serial administration of cognitive tests is increasingly common, there is a paucity of research on test-retest reliabilities and practice effects, both of which are important for evaluating changes in functioning. Reliability is generally conceptualized as involving short-lasting changes in performance. However, when repeated testing occurs over a period of years, there will be some longer lasting effects. The implications of these longer lasting effects and practice effects on reliability were examined in the context of repeated administrations of the Wechsler Memory Scale-III in 339 community-dwelling women aged 40-79 years over 2 to 7 years. The results showed that Logical Memory and Verbal Paired Associates subtests were consistently the most reliable subtests across the age cohorts. The magnitude of practice effects varied as a function of subtests and age. The largest practice effects were found in the youngest age cohort, especially on the Faces, Logical Memory, and Verbal Paired Associates subtests.     

Increasing the reliability of Wechsler Intelligence Scale for Children--Third Edition difference scores with reliable component analysis

Wechsler Intelligence Scale for Children--Third Edition index score differences are generally interpreted cautiously, if at all, primarily because of their poor reliability. On the basis of prior analyses with the Wechsler Adult Intelligence Scale--Third Edition (J. C. Caruso & N. Cliff, 1999), it was hypothesized that differences between scores defined by reliable component analysis would have higher reliability than those defined by traditional equal weighting. Differences between the reliable component scores showed substantially higher reliability than equally weighted score differences. The differences between reliable component scores were also substantially more reliable than those derived from the weighted scores suggested by K. C. H. Parker and L. Atkinson (1994). Using the weights provided in this article will allow researchers and practitioners to compute the RCA scores and have the assurance of high reliability with its attractive consequences.     

Utility of the MMPI in a geriatric population

Despite the popularity of the Minnesota Multiphasic Personality Inventory (MMPI), there exists a relative dearth of normative and validity research regarding its use with persons over the age of 60. Our investigation was designed to examine the MMPI performance of both a normal and a clinical sample of older men and women. Specifically, a nonpatient community sample of 204 subjects and an outpatient psychiatric sample of 30 subjects, between the ages of 60 and 90, were administered the MMPI as well as structured psychiatric interview, the Psychiatric Status Schedule (PSS). Results revealed that, on most of the MMPI scales, the mean scores were well above the norms (i.e., 5-10 t-score points). Through comparisons between the clinical and community subjects as well as between MMPI and PSS performance, the MMPI demonstrated substantial discriminative and concurrent criterion validity within this geriatric sample. The results of the study suggest that, with a few important exceptions, the MMPI, as generally utilized, is valid for use in the geriatric population.     

Abbreviated form of the Wechsler Memory Scale-III Faces subtest

A major criticism of the Wechsler Memory Scale-III Faces subtest is the number of items, which can be daunting and time-consuming for an impaired client or boring for a normal client. An analysis of several versions, with data from a sample of 50 clinical referrals, revealed that a 32-item subtest was best overall. Using this version, 100% (Faces I) and 94% (Faces II) of the predicted raw scores were less than 4 points away from the actual raw scores, whereas 66% (Faces I) and 70% (Faces II) were less than 2 points away. Limitations of this procedure are discussed.     

Correlations for Wechsler Intelligence Scale for Children--Revised and the Wechsler Preschool and Primary Scale of Intelligence for Iranian children.

This study focused on the relationship between the Wechsler Intelligence Scale for Children--Revised (WISC--R) and the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) given to 40 6-yr.-old Iranian children. Pearson correlations between the WISC--R and the WPPSI IQs and between scaled scores on the corresponding subtests were significant. The comparison of mean IQs and scaled scores indicates that the WISC--R yielded a significantly higher Verbal IQ and higher scores on Information, Vocabulary, Comprehension, and Picture Completion than the WPPSI. The mean difference between corresponding Verbal and Full Scale IQs was not significant. These results suggest that scores on the two instruments correlated well for these 6-yr.-old Iranian children and the content on which IQs for the recently restandardized WISC--R and WPPSI are based are related.     

Parsimonious prediction of Wechsler Memory Scale--III memory indices

Equations for prorating the Wechsler Memory Scale--III (WMS-III) Index scores were derived and validated on a sample of 252 mixed clinical cases. Regression equations were performed using age-scaled scores as predictors and the sum of age-scaled scores for Immediate Memory (IM) and General Memory (GM) as the criteria. Including Logical Memory and Verbal Paired Associates with either Faces or Family Pictures resulted in estimated scores that accounted for 95% to 97% of the variance for IM and GM. Over 80% of these cases had estimated sum of scaled scores that fell within 3 points of actual sum of scaled scores, within 1 standard error of measurement. When only Logical Memory and Verbal Paired Associates were included, estimations accounted for only 87% of the variance, and only 60% of the estimated scores fell within 3 points of actual sum of scaled scores. The regression equations are presented, as are the confidence intervals derived from a bootstrapping procedure that created 15,000 different samples.     

Psychosocial enhancement of immunocompetence in a geriatric population

This study assessed the enhancement of immunocompetence by relaxation and social contact in 45 geriatric residents of independent-living facilities. Subjects were randomly assigned to one of three protocols: relaxation training, social contact, or no contact. Subjects in the relaxation and social-contact conditions were seen individually three times a week for a month. Blood samples and self-report data were obtained at baseline, at the end of the intervention, and at a 1-month follow-up. At the end of the intervention, the relaxation group showed a significant increase in natural killer cell activity, and significant decreases in antibody titers to Herpes simplex virus and self-rated distress; the other two groups showed nonsignificant changes. There was a general increase in the T-lymphocyte response to phytohemagglutinin stimulation at the end of the intervention, with greater change at lower mitogen concentrations. These data suggest that cellular immunocompetence may be enhanced by psychosocial interventions.     

Construct validity of the Bender-Gestalt II: comparison with Wechsler Intelligence Scale for Children-III

This study investigated the relationships of visuomotor constructs as measured by the Bender-Gestalt II with the subtests of the WISC-III. A factor analysis included the standardized Copy and Recall scores of the Bender-Gestalt II and subtest scores of the WISC-III. The Copy score was predicted to load on measures of visual and spatial thinking and the Recall score on a short-term memory factor. The results of a principal components analysis suggest a four-factor solution with the Bender-Gestalt II Copy score loading on a visual and spatial thinking factor primarily with WISC-III Perceptual Organization subtests. The Recall score loaded on a visual and spatial thinking factor as well as a short-term memory factor with the WISC-III Digit Span subtest. The results suggest the Bender-Gestalt II Copy subtest shared commonality with the visual and spatial tasks given the similarity in the visuomotor demands of each test and was less influenced by processing speed or cultural knowledge than other tests on the visual and spatial thinking factor. Also, results suggest Bender-Gestalt II Recall measures elements of both visual and spatial thinking as well as aspects of short-term memory and memory retrieval. Clinical guidelines for co-administration and underlying processing demands are discussed.     

Ego development and intelligence in a psychiatric population: Wechsler subtest scores

The relationship between Loevinger's measure of ego development and the Wechsler Intelligence Scales subtest scores was investigated in 91 adolescent and young adult psychiatric inpatients. Correlations with Verbal IQ and verbal subtests in general were positive and significant. The correlation with the Comprehension subtest was the highest and remained significant when Full Scale IQ was partialled. Post-conformists obtained the highest mean scores on Picture Arrangement; however, there was no difference among the lower stages on this subtest. The results lend support to a social reasoning component of ego development.     

The utility of the spatial span in a clinical geriatric population

Spatial Span subtest of the Wechsler Memory Scale has been viewed as an indicator of working memory and visuospatial processing. The current study examined the impact of cognitive impairment and its severity on Spatial Span performance. A neuropsychological battery including Spatial Span was administered to 538 individuals (65-89) who were grouped by consensus into Alzheimer's disease, Vascular Dementia, Amnestic Mild Cognitive Impairment, Non-Amnestic Mild Cognitive Impairment and cognitively normal. Increase in level of impairment resulted in a decrease in Spatial Span Total Score. A weak relationship between age and Spatial Span Total Score was found. Spatial Span Forward remains relatively stable regardless of level of impairment. Spatial Span Backward was more sensitive to severity. No significant differences were found between individuals diagnosed with Alzheimer's disease and those with Vascular Dementia suggesting similar deficit patterns in the cognitive abilities measured by the Spatial Span. Mild Cognitive Impairment groups and normals did not differ suggesting visuospatial processes are not affected early in the dementing process.