Wechsler Memory Scale-Fourth Edition Research Articles

Practice effect and test–retest reliability of the Wechsler Memory Scale-Fourth Edition in people with dementia

BackgroundThe Wechsler Memory Scale-Fourth Edition (WMS-IV) has been widely used to assess memory function in people with dementia. The older adult battery of the WMS-IV includes four indices and seven subtests. The aims of this study were to examine the practice effect and test–retest reliability and calculate the reliable change index modified for practice (RCIp) for the indices and subtests of the older adult battery of the WMS-IV for people with dementia.MethodsFifty-six participants completed the WMS-IV twice, two weeks apart. The practice effect was investigated using effect size (Cohen’s d) and bootstrapping mixed design analysis of variance while considering the severity of dementia. The test–retest reliability was estimated using intraclass correlation coefficient (ICC).ResultsThe results showed non-significant practice effects with Cohen’s d < 0.20 in different severities of dementia on two indices and five subtests. The ICC values of these indices and subtests were 0.82–0.85 and 0.57–1.00, respectively. The other two indices (i.e., auditory memory and immediate memory) and two subtests (i.e., logical memory delayed recall and visual reproduction immediate recall) demonstrated small to moderate practice effect (d = 0.46–0.74) for people with mild severity of dementia.ConclusionOn the whole, the WMS-IV has no to moderate practice effects and moderate to excellent test–retest reliability in people with dementia. The values of the RCIp with 95% confidence interval for the indices and subtests were provided in this study, which are useful to clinicians and researchers for interpreting the real score change in persons with dementia. The two indices (i.e., auditory memory and immediate memory) and two subtests (i.e., logical memory delayed recall and visual reproduction immediate recall) with noticeable practice effect should be used with caution when assessing memory function repeatedly in people with mild severity of dementia.

Wechsler memory scale–fourth edition (WMS–IV) in the neuropsychological evaluation of patients diagnosed with probable Alzheimer’s disease

There is a scarcity of research concerning Wechsler Memory Scale–Fourth Edition (WMS–IV) findings in Alzheimer’s disease (AD). We provide information, beyond that in the test manual, concerning the power of the scale to detect AD-associated memory deficits. Participants were 87 individuals with diagnoses made according to criteria specified in the Fifth Edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5): 31 probable neurocognitive disorders due to AD and 33 patients with depression. Twenty-three elderly controls were also studied. The depressed and control participants had similar demographics as well as test scores and therefore were blended into a single control group (n = 56). AD patients were significantly impaired on the four WMS–IV indexes relative to controls, and the index pattern of performance differed across groups. Delayed Memory Index was a significant weakness in AD, whereas the Visual Memory Index was the lowest mean for controls. Sensitivity, specificity, hit rate, positive predictive value, and negative predictive value were strong to excellent for each index when a cutoff of 1.5 SDs below the normative mean was used to separate ADs and controls. Receiver operating characteristics curve analyses yielded excellent area under the curve statistics that ranged from .970 for the Visual Memory Index to .999 for the Delayed Memory Index. A supplementary analysis yielded similar results when the AD group was divided into mild (n = 10) and major (n = 21) subgroups.

Performance of Patients with Relapsing-Remitting Multiple Sclerosis on the Wechsler Memory Scale-Fourth Edition (WMS-IV): Preliminary Clinical Findings

Historically, the Wechsler Memory Scales have been one of the most commonly used measures of memory in clinical neuropsychological evaluations. There are limited published reports, however, analyzing the performance of patients with multiple sclerosis (MS) on the Fourth Edition of the test. The aim of this investigation was to describe the utility of the Wechsler Memory Scale-Fourth Edition (WMS-IV) in detecting and characterizing the memory deficits associated with relapsing-remitting MS. Thirty-four outpatients with clinically definite relapsing-remitting MS were administered the WMS-IV and Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV). Means for age, education, and duration of MS diagnosis were 43.15, 14.88, and 8.41 years, respectively. Index scores did not differ significantly across the five WMS-IV domains. Comparison of actual WMS-IV indexes with those predicted by the WAIS-IV General Ability Index revealed that in every instance predicted index means were significantly higher than actual index means. Only 6 (17.6%) of 34 patients had all five actual and predicted index scores at comparable levels; whereas, 28 (82.4%) had ≥ 1 actual indexes significantly below the predicted level. Contrary to prior research using earlier versions of these measures, more patients demonstrated relatively reduced performances on the WMS-IV Visual Working Memory Index than on the WAIS-IV Processing Speed Index. Results support the use of the WMS-IV in evaluating learning and memory in individuals with MS. Findings also challenge the notion that the information processing deficits in MS are more reflective of reduced processing speed than impaired working memory.

Analysis of Story Recall in Military Veterans With and Without Mild Traumatic Brain Injury: Preliminary Results.

The purpose of this study was to determine whether detailed analysis of story recall performance reveals significant differences between veterans with and without history of mild traumatic brain injury (mTBI). Twenty-one military veterans participated, with 7 reporting history of mTBI. All participants were administered the Logical Memory I and II subtests from the Wechsler Memory Scale-Fourth Edition (Wechsler, 2009). Responses were scored for total correct ideas (TCI) and total words produced (TWP). Although the groups did not differ in scaled scores, other measures did reveal significant differences. After a delay, the mTBI group showed a greater drop in TCI relative to the control group. Additionally, the control group showed an increase in TWP when the recall was delayed versus immediate; a pattern not observed for the mTBI group. The mTBI and control groups did not significantly differ in scaled scores. However, group differences were observed in TCI and TWP. The findings suggest that, relative to the control group, the mTBI group were less successful in retrieving episodic information and eliciting self-cueing. Small sample size limited data interpretation, and larger sample sizes are needed to confirm the findings. The results indicate that veterans with mTBI may present with symptoms persisting beyond the acute state of the injury.

Evaluating the accuracy of the Wechsler Memory Scale-Fourth Edition (WMS-IV) logical memory embedded validity index for detecting invalid test performance

ABSTRACTEmbedded performance validity tests (PVTs) allow for continuous assessment of invalid performance throughout neuropsychological test batteries. This study evaluated the utility of the Wechsler Memory Scale-Fourth Edition (WMS-IV) Logical Memory (LM) Recognition score as an embedded PVT using the Advanced Clinical Solutions (ACS) for WAIS-IV/WMS-IV Effort System. This mixed clinical sample was comprised of 97 total participants, 71 of whom were classified as valid and 26 as invalid based on three well-validated, freestanding criterion PVTs. Overall, the LM embedded PVT demonstrated poor concordance with the criterion PVTs and unacceptable psychometric properties using ACS validity base rates (42% sensitivity/79% specificity). Moreover, 15–39% of participants obtained an invalid ACS base rate despite having a normatively-intact age-corrected LM Recognition total score. Receiving operating characteristic curve analysis revealed a Recognition total score cutoff of < 61% correct improved specificity (92%) while sensitivity remained weak (31%). Thus, results indicated the LM Recognition embedded PVT is not appropriate for use from an evidence-based perspective, and that clinicians may be faced with reconciling how a normatively intact cognitive performance on the Recognition subtest could simultaneously reflect invalid performance validity.

Testing Spearman's hypotheses using a bi-factor model with WAIS-IV/WMS-IV standardization data

Spearman's hypothesis (SH) is a phrase coined by Arthur Jensen, which posits that the size of Black–White mean differences across a group of diverse mental tests is a positive function of each test's loading onto the general intelligence (g) factor. Initially, a correlated vector (CV) approach was used to examine SH, where the results typically confirmed that the magnitude of g loadings were positively correlated with the size of mean group differences in the observed test scores. The CV approach has been heavily criticized by scholars who have argued that a more precise method for examining SH can be better investigated using a multi-group confirmatory factor analysis (MG-CFA). Studies of SH using MG-CFA have been much more equivocal, with results not clearly confirming nor disconfirming SH.In the current study, we argue that a better method for extracting g in both the CV and MG-CFA approaches is to use a bi-factor model. Because non-g factors extracted from a bi-factor approach are independent of g, the bi-factor model allows for a robust examination of the influence of g and non-g factors on group differences on mental test scores. Using co-normed standardization data from the Wechsler Adult Intelligence Scale-Fourth Edition and the Wechsler Memory Scale-Fourth Edition, we examined SH using both CV and MG-CFA procedures. We found support for the weak form of SH in both methods, which suggests that both g and non-g factors were involved in the observed mean score differences between Black and White adults.

Confirmatory Factor Analysis of the Dutch Version of the Wechsler Memory Scale-Fourth Edition (WMS-IV-NL).

The latent factor structure of the Dutch version of the Wechsler Memory Scale-Fourth Edition (WMS-IV-NL) was examined with a series of confirmatory factor analyses. As part of the Dutch standardization, 1,188 healthy participants completed the WMS-IV-NL. Four models were tested for the Adult Battery (16-69 years; N = 699), and two models were tested for the Older Adult Battery (65-90 years; N = 489). Results corroborated the presence of three WMS-IV-NL factors in the Adult Battery consisting of Auditory Memory, Visual Memory, and Visual Working Memory. A two-factor model (consisting of Auditory Memory and Visual Memory) provided the best fit for the data of the Older Adult Battery. These findings provide evidence for the structural validity of the WMS-IV-NL, and further support the psychometric integrity of the WMS-IV.

The Interchangeability of CVLT-II and WMS-IV Verbal Paired Associates Scores: A Slightly Different Story.

We investigated the similarity of the Wechsler Memory Scale-Fourth Edition (WMS-IV) Auditory Memory Index (AMI) scores when California Verbal Learning Test-Second Edition (CVLT-II) scores are substituted for WMS-IV Verbal Paired Associates (VPA) subtest scores. College students (n = 103) were administered select WMS-IV subtests and the CVLT-II in a randomized order. Immediate and delayed VPA scaled scores were significantly greater than VPA substitute scaled scores derived from CVLT-II performance. At the Index level, AMI scores were significantly lower when CVLT-II scores were used in place of VPA scores. It is important that clinicians recognize the accepted substitution of CVLT-II scores can result in WMS-IV scores that are inconsistent with those derived from standard administration. Psychometric issues that plausibly contribute to these differences and clinical implications are discussed.

Apparently Abnormal Wechsler Memory Scale Index Score Patterns in the Normal Population

Interpretation of the Wechsler Memory Scale-Fourth Edition may involve examination of multiple memory index score contrasts and similar comparisons with Wechsler Adult Intelligence Scale-Fourth Edition ability indexes. Standardization sample data suggest that 15-point differences between any specific pair of index scores are relatively uncommon in normal individuals, but these base rates refer to a comparison between a single pair of indexes rather than multiple simultaneous comparisons among indexes. This study provides normative data for the occurrence of multiple index score differences calculated by using Monte Carlo simulations and validated against standardization data. Differences of 15 points between any two memory indexes or between memory and ability indexes occurred in 60% and 48% of the normative sample, respectively. Wechsler index score discrepancies are normally common and therefore not clinically meaningful when numerous such comparisons are made. Explicit prior interpretive hypotheses are necessary to reduce the number of index comparisons and associated false-positive conclusions. Monte Carlo simulation accurately predicts these false-positive rates.

Development of Alternate Paragraphs for the Logical Memory Subtest of the Wechsler Memory Scale-IV

The purpose of the two studies included in this article was to validate an alternate form, the Morris Revision-Fourth Edition (MR-IV), to the Logical Memory paragraphs of the Wechsler Memory Scale-Fourth Edition (LM-IV) for use when retesting of individuals is desired. Study I demonstrated high correlation with the LM-IV paragraphs. Study II was a replication that again demonstrated high correlation between the original LM-IV and the new MR-IV paragraphs. High interrater reliability also was demonstrated. Consequently, the MR-IV paragraphs can be considered an alternate form to the LM-IV paragraphs. Although other attempts have been made to develop alternate stories, these new paragraphs are the only ones that are equivalent in structure, affective tone, and number of scorable units. They have considerable clinical utility and research potential.

Administration of Neuropsychological Tests Using Interactive Voice Response Technology in the Elderly: Validation and Limitations

Interactive voice response (IVR) systems are computer programs, which interact with people to provide a number of services from business to health care. We examined the ability of an IVR system to administer and score a verbal fluency task (fruits) and the digit span forward and backward in 158 community dwelling people aged between 65 and 92 years of age (full scale IQ of 68–134). Only six participants could not complete all tasks mostly due to early technical problems in the study. Participants were also administered the Wechsler Intelligence Scale fourth edition (WAIS-IV) and Wechsler Memory Scale fourth edition subtests. The IVR system correctly recognized 90% of the fruits in the verbal fluency task and 93–95% of the number sequences in the digit span. The IVR system typically underestimated the performance of participants because of voice recognition errors. In the digit span, these errors led to the erroneous discontinuation of the test: however the correlation between IVR scoring and clinical scoring was still high (93–95%). The correlation between the IVR verbal fluency and the WAIS-IV Similarities subtest was 0.31. The correlation between the IVR digit span forward and backward and the in-person administration was 0.46. We discuss how valid and useful IVR systems are for neuropsychological testing in the elderly.

Predictors of Successful Communication With Interactive Voice Response Systems in Older People

Interactive voice response (IVR) systems are computer programs that can interact with people to provide a number of services from business to health care. However, surveys examining people's attitudes toward these systems have consistently found that people in general and older people in particular strongly dislike these systems. We wanted to determine the memory and cognitive abilities that predict successful IVR interactions for older people. We compared the performance of 185 older adults (aged 65 and older) on normed cognitive tests (the Wechsler Adult Intelligence Scale fourth edition and the Wechsler Memory Scale fourth edition) with their performance on 4 real-life IVR systems that included fact-finding at governmental agencies and plane ticket reservation. The results indicated that adults aged 65 and older experience significant difficulties in interacting with IVR systems. A significant number of people (20.5%) could not complete any of the tasks. Participants who could not complete any task were older and had the lowest full-scale IQ. However, there was little difference between the age of participants who completed 1, 2, 3, or 4 tasks. Rather, auditory memory and working memory were the best overall predictors for success in IVR tasks. The impact of poorer auditory memory and working memory is compounded by programming practices that increase the demand on these abilities and create unnecessary difficulties. Successful use of IVR systems could eventually complement in person health services.

Detection of Suboptimal Effort with Symbol Span: Development of a New Embedded Index

Developing embedded indicators of suboptimal effort on objective neurocognitive testing is essential for detecting increasingly sophisticated forms of symptom feigning. The current study explored whether Symbol Span, a novel Wechsler Memory Scale-fourth edition measure of supraspan visual attention, could be used to discriminate adequate effort from suboptimal effort. Archival data were collected from 136 veterans classified into Poor Effort (n = 42) and Good Effort (n = 94) groups based on symptom validity test (SVT) performance. The Poor Effort group had significantly lower raw scores (p < .001) and age-corrected scaled scores (p < .001) than the Good Effort group on the Symbol Span test. A raw score cutoff of <14 produced 83% specificity and 50% sensitivity for detection of Poor Effort. Similarly, sensitivity was 52% and specificity was 84% when employing a cutoff of <7 for Age-Corrected Scale Score. Collectively, present results suggest that Symbol Span can effectively differentiate veterans with multiple failures on established free-standing and embedded SVTs.

Confirmatory Factor Analysis of the WAIS-IV/WMS-IV

The Wechsler Adult Intelligence Scale-fourth edition (WAIS-IV) and the Wechsler Memory Scale-fourth edition (WMS-IV) were co-developed to be used individually or as a combined battery of tests. The independent factor structure of each of the tests has been identified; however, the combined factor structure has yet to be determined. Confirmatory factor analysis was applied to the WAIS-IV/WMS-IV Adult battery (i.e., age 16-69 years) co-norming sample (n = 900) to test 13 measurement models. The results indicated that two models fit the data equally well. One model is a seven-factor solution without a hierarchical general ability factor: Verbal Comprehension, Perceptual Reasoning, Processing Speed, Auditory Working Memory, Visual Working Memory, Auditory Memory, and Visual Memory. The second model is a five-factor model composed of Verbal Comprehension, Perceptual Reasoning, Processing Speed, Working Memory, and Memory with a hierarchical general ability factor. Interpretative implications for each model are discussed.