Delayed recall on the Wechsler memory scale-revised: The factor structure revisited

Although delayed recall tasks are prominent features of the popular Wechsler Memory Scale-Revised (WMS-R), exploratory factor analyses consistently have failed to identify an associated delayed recall factor. The present study tested the hypothesis (Elwood, 1991b) that a delayed recall factor could be found by substituting percent retained (saving) scores for the existing WMS-R delayed recall subtest scores. Principal component analyses of age-corrected WMS-R immediate and save scores in a mixed clinical sample failed to find the hypothesized save factor. Both the scree and MAP tests retained one general memory factor, which accounted for 42.2% of the total variance. Independent statistical programs produced essentially equivalent results. Clinical implications of these findings are discussed.     

Discriminating between simulated malingering and closed head injury on the Wechsler memory scale-revised

We tested the hypothesis that malingering is distinguished by poorer performance on recognition relative to recall tasks by evaluating the ability of discriminant functions to distinguish between 89 subjects simulating malingering and 44 subjects with a history of closed head injury (CHI) on the Wechsler Memory Scale - Revised (WMS-R). Functions with good accuracy in discriminating between simulated malingerers and controls in prior studies did not have adequate specificity when applied to the CHI group. A newly derived discriminant function achieved overall classification accuracy of 79% for the malingering versus CHI groups on cross-validation, with 79% sensitivity (true positives for malingering) and 80% specificity (true negatives for closed head injured). A complex performance pattern on seven WMS-R subtests distinguished malingering subjects from those with CHI, but did not support the recognition versus recall hypothesis. The malingering pattern involved: (a) power performance on two relatively (but inconspicuously) easy tasks dependent on immediate recall (Visual Reproduction I and Visual Memory Span); (b) better performance on two relatively (but inconspicuously) easy tasks dependent on immediate recall (Visual Paired Associates I and Digit Span); (c) poorer performance on two relatively difficult delayed tasks (Logical Memory II and Visual Paired Associates II); and (d) better performance on another difficult task involving delayed recall (Visual Reproduction II).     

Factor structure of the WAIS-R by educational level: an examination of elderly persons.

A factor analysis of the WAIS-R by educational level for persons 75 years and older was conducted. Two- and three-factor solutions were generated for persons with 0 to 11 years of education and for high school graduates. A two-factor solution composed of verbal and perceptual-organization factors best explained the WAIS-R scores for subjects with 11 or fewer years of education. However, a three-factor solution emerged for persons with 12 or more years of schooling and consisted of the verbal comprehension, perceptual-organization, and freedom from distractibility factors. Clinicians must be aware of the potentially different factor structures generated by educational level to provide the most accurate interpretation of WAIS-R scores for elderly persons.     

Validity of the verbal IQ as a short form of the Wechsler adult intelligence scale-revised

Assessed the validity of the Verbal IQ as a short form of the WAIS-R. Ss were 104 psychiatric patients with means for age, education, and Full Scale IQ of 36.22 (SD = 9.04), 12.46 (SD = 1.98), and 93.94 (SD = 12.19), respectively. A correlation of 0.93 (p < 0.001) between the Verbal and Full Scale IQs was found. The average Verbal IQ exceeded the average Full Scale IQ by a small (i. e., 1.65 IQ points) but statistically significant amount (p < 0.001). Thirty-three (32%) Ss showed changes in their intelligence categories when the Verbal IQ was compared to the Full Scale IQ. However, when the Verbal IQ was banded by the standard error of measurement (SE_M = ± 3) and the precision range was compared to the Full Scale IQ, results indicated 88% agreement. If clinicians must rely on the Verbal IQ as an estimate of the Full Scale, reporting the score in conjunction with a precision range will increase its accuracy.     

韦氏智力量表因素建构的再分析

韦氏智力量表因素建构的再分析资料进行了再分析，结果发现：（１）ｇ因素在三套韦氏量表各分测验上均有中等以上的负荷，方差贡献率达４０％以上；（２）言语分测验主要负荷Ａ因素，操作分测验主要负荷Ｂ因素，在三因素模式中，背数和译码负荷Ｃ因素，但幼儿量表的因素模式不够清楚；（３）韦氏智力量表具有较好的跨人群和跨文化结构效度。最后，从神经心理学角度，对各因素意义作了尝试性解释。     

Factor analysis of the Wechsler memory scale: Is the associate learning subtest an unclear measure?

A factor analysis of the Wechsler Memory Scale (WMS) with 30-minute delayed recall scores (percent retained) for the Logical Memory, Visual Reproduction, and Associate Learning subtests indicated that this variant of the WMS taps different types of learning and memory for new material. With regard to the verbal learning/recall subtests, Logical Memory appears to be related to attention/ concentration ability, while Associate Learning is relatively independent. The results also showed that both the easy and hard items from Associate Learning tap the same ability, providing evidence that this subtest is a measure of rote verbal learning. These results support the clinical utility of the WMS with delayed recalls in neuropsychiatric populations.     

Factor analysis of the Wechsler Memory Scale and the Warrington Recognition Memory Test.

Subjects were 156 individuals referred, for psychological and neuropsychological evaluation. The Wechsler Memory Scale (WMS) including the 12h delayed condition of Russell's revision and Warrington's Recognition Memory Test (RMT) were administered as part of each evaluation. Using scores from the RMT subtests: (1) Memory for Words and (2) Memory for Faces, and scores from the WMS subtests: (3) Logical Memory, (4) Digit Span, (5) Visual Reproduction, and (6) Associate Learning flow associate pairs only), a principal components factor analysis was carried out with an orthogonal varimax rotation yielding four factors: (1) verbal learning and memory, (2) Figurai memory, (3) Recognition memory, and (4) Attention-Concentration. Results are discussed with respect to the independent, but complementary information provided by the WMS and RMT for measurement of memory functions.     

Effects of unilateral lesions of the Wechsler memory scale

Compared 10 Ss with confirmed unilateral lesions in the right or left hemisphere on subtests of the Wechsler Memory Scale (WMS). The groups were comparable in terms of age, sex, education, Full Scale IQ and Memory Quotient. Contrary to previous studies, it was found that the WMS was sensitive to the effects of unilateral lesions when the pattern of deficits on the subtests was examined. The same subtests that have been shown to discriminate between controls and brain-injured Ss also were sensitive to unilateral lesions.     

Secular trends in male adult height 1904-1996 in relation to place of residence and parent's educational level in Portugal.

The records of height of 22841 18-year-old Portuguese males were analysed as well as their parents educational level and localities of subject's residence (districts). The sample includes all the Portuguese 18-year-old males, born in 1978 and examined in 1996, in central and southern Portugal, representing all the social strata. Statistically significant differences (p < or = 0.001) among the districts were found: males from Setúbal (172.75 cm) and Lisboa (172.64 cm), the most developed districts, are the tallest, and those from C. Branco (170.79cm) and Coimbra (171.19 cm) are the shortest. Comparing to published data from 1904, a positive secular trend in height was found. The average increase was 8.99 cm, which yields a rate of 0.99 cm per decade. This positive trend must be related to the general improvement in the population's standard living conditions, as the striking drop of post-neonatal mortality rate shows after the 1960s and 1970s. Despite this positive trend, great social difference still exists: the gap between the two extremes of parents' educational level is almost 4 cm for height. Analysis of variance (ANOVA) showed significant effects of father's and mother's educational level as well as subject's locality of residence, but the influence of parents' educational level was stronger than that of geographic residence. These results suggest that the secular trend in height will continue for the Portuguese population in the future decade.     

Morphometric evaluation of the frontal sinus in relation to age.

To investigate the development of the frontal sinus size during life, we studied the planar morphometry in 60 frontal radiographs of patients of different age and gender. A professional software (Bersoft Image 4.02) was used to measure the frontal area of the right and left frontal sinuses on radiographic images. A frontal sinus was already evident in 4-year-old children. Unilateral or bilateral absence of the frontal sinus was seen in 5% of cases. The size of the sinusal area increases up to 19-year-old patients, synchronous with general craniofacial growth. In adults, individual differences in size and shape occurred in relation to environmental factors. In some elderly patients, osseous resorption led to an enlargement of the frontal sinus that might complicate surgical procedures performed in this area.     

Detection of changes in material-specific memory following temporal lobectomy using the Wechsler Memory Scale-Revised.

To determine the utility of the Wechsler Memory Scale-Revised (WMS-R) in measuring material-specific memory changes, within-subject comparisons of the Verbal-Visual Memory Index discrepancy and discrepancy scores using short-term and delayed Logical Memory and Visual Reproduction subtests from the WMS-R were studied prior to and following temporal lobectomy among 30 patients with left temporal lobectomy, 30 with right temporal lobectomy, and 50 epileptic, non-surgical controls. The groups were matched on age, sex, handedness, age at seizure onset, duration of epilepsy, and presurgical Verbal and Performance IQ; the right temporal group had a higher mean educational level (p <.05). All surgical patients were left hemisphere dominant for speech; those who had persistent postoperative seizures were excluded from study. On retesting, left temporal lobectomy was associated with a marked change in short-term and delayed memory discrepancy scores primarily due to a drop in verbal memory. Right temporal lobectomy was not associated with a drop in visual memory, suggesting that the WMS-R appears to reflect decrements in material-specific memory following left but not right temporal lobectomy. The nonsurgical controls showed increases in both short-term and delayed memory discrepancy scores due to increases in short-term and delayed verbal memory. Relative to these controls, the absence of comparable increases in verbal memory among the right temporal patients suggests that right temporal lobectomy may be associated with risk to verbal memory.