Amsterdam Short-Term Memory Test Research Articles

Validity of the Groningen Effort Test in patients with suspected chronic solvent-induced encephalopathy.

The use of performance validity tests (PVTs) in a neuropsychological assessment to determine indications of invalid performance has been a common practice for over a decade. Most PVTs are memory-based; therefore, the Groningen Effort Test (GET), a non-memory-based PVT, has been developed. This study aimed to validate the GET in patients with suspected chronic solvent-induced encephalopathy (CSE) using the criterion standard of 2PVTs. A second goal was to determine diagnostic accuracy for GET. Sixty patients with suspected CSE referred for NPA were included. The GET was compared to the criterion standard of 2PVTs based on the Test of Memory Malingering and the Amsterdam Short Term Memory Test. The frequency of invalid performance using the GET was significantly higher compared to the criterion of 2PVTs (51.7% vs. 20.0% respectively; p < 0.001). For the GET index, the sensitivity was 75% and the specificity was 54%, with a Youden's Index of 27. The GET showed significantly more invalid performance compared to the 2PVTs criterion suggesting a high number of false positives. The general accepted minimum norm of specificity for PVTs of >90% was not met. Therefore, the GET is of limited use in clinical practice with suspected CSE patients.

Performance Validity and Outcome of Cognitive Behavior Therapy in Patients with Chronic Fatigue Syndrome

There is limited research examining the impact of the validity of cognitive test performance on treatment outcome. All known studies to date have operationalized performance validity dichotomously, leading to the loss of predictive information. Using the range of scores on a performance validity test (PVT), we hypothesized that lower performance at baseline was related to a worse treatment outcome following cognitive behavioral therapy (CBT) in patients with Chronic Fatigue Syndrome (CFS) and to lower adherence to treatment. Archival data of 1081 outpatients treated with CBT for CFS were used in this study. At baseline, all patients were assessed with a PVT, the Amsterdam Short-Term Memory test (ASTM). Questionnaires assessing fatigue, physical disabilities, psychological distress, and level of functional impairment were administered before and after CBT. Our main hypothesis was not confirmed: the total ASTM score was not significantly associated with outcomes at follow-up. However, patients with a missing follow-up assessment had a lower ASTM performance at baseline, reported higher levels of physical limitations, and completed fewer therapy sessions. CFS patients who scored low on the ASTM during baseline assessment are more likely to complete fewer therapy sessions and not to complete follow-up assessment, indicative of limited adherence to treatment. However, if these patients were retained in the intervention, their response to CBT for CFS was comparable with subjects who score high on the ASTM. This finding calls for more research to better understand the impact of performance validity on engagement with treatment and outcomes.

Memory deficits in patients with major depression: yes, they are trying hard enough!

ABSTRACTBackground: Cognitive impairment is a common symptom of patients with Major Depression (MDD) with negative clinical and social effects. With this study we investigated the question of whether MDD patients’ effort to memorize items is reduced and whether this reduction is related to patients’ memory impairment.Research design and methods: Twenty-two patients with MDD and 28 healthy control participants took part in the study. Both groups did not differ with respect to age, gender, and basic education. MDD was confirmed by the Mini Diagnostic Interview for Mental Disorders (Mini-DIPS). Willingness to make an effort was assessed by the Amsterdam Short-Term Memory Test (ASTM). Logical Memory (LM) from the Wechsler Memory Scale (WMS IV) was used to assess verbal memory.Results: With respect to the willingness to make an effort, all MDD-patients performed above the cutoff and did not perform worse than healthy control participants. Depression appears to have a negative impact on recall and recognition of verbal information, but the effect on recall was larger.Conclusions: These findings support studies indicating no motivational deficits in patients with depression during standardized neuropsychological testing. Reduced motivation is not a plausible explanation for depressive patients’ cognitive deficits assessed with neuropsychological tests.

Symptom validity testing (SVT) and social security disability claims

Background and aimsOver 50% of adult disability claimants fail some form of SVT. While some over report psychological, affective symptoms, others may report incredible cognitive symptoms. We examined effects of different types of response bias on free recall and self-reported depression.Participants and methods This is a single site cross-sectional study using a convenience sample (n = 224) of disability claimants in the Netherlands. The Green Word Memory Test (GWMT) was administered to all subjects. The Amsterdam Short Term Memory Test (AKTG), the Structured Inventory of Malingered. Symptomatology (SIMS), and the beck depression inventory (BDI-II) were administered in subsamples. Participant classification according to GWMT and SIMS outcomes resulted in four groups, G+/S+, G+/S−, G−/S+ and G−/S−.ResultsAverage age of the participants was 46.3 years (SD 9.9), 41.5% were female, and 43% were higher educated. GWMT was positive in 48.2% of all subjects, and 27.6% scored positive on both GWMT and SIMS. Analysis of variance of GWMT Free recall and Beck depression scores showed significant group differences [F(3, 123) = 33.21, P = .000] and [F(3, 106) = 25.17, P = .000] respectively.ConclusionsNon credible test performance was prevalent in this Dutch study of disability claimants. Insufficient effort and over reporting of psychological symptoms are associated with different score profiles on regular tests and self-rating scales.Disclosure of interestThe author receives funding for his work as a neuropsychologist in an expertise setting.

Poor symptom and performance validity in regularly referred Hospital outpatients: Link with standard clinical measures, and role of incentives

We investigated the frequency of symptom validity test (SVT) failure and its clinical correlates in a large, heterogeneous sample of hospital outpatients referred for psychological assessment for clinical purposes. We studied patients (N=469), who were regularly referred for assessment to the psychology departments of five hospitals. Background characteristics, including information about incentives, were obtained with a checklist completed by the clinician. As a measure of over-reporting, the Structured Inventory of Malingered Symptomatology (SIMS) was administered to all patients. The Amsterdam Short-Term Memory test (ASTM), a cognitive underperformance measure, was only administered to patients who were referred for a neuropsychological assessment. Symptom over-reporting occurred in a minority of patients, ranging from 12% to 19% in the main diagnostic patient groups. Patients with morbid obesity had a low rate of over-reporting (1%). The SIMS was positively associated with levels of self-reported psychological symptoms. Cognitive underperformance occurred in 29.3% of the neuropsychological assessments. The ASTM was negatively associated with memory test performance. We found no association between SVT failure and financial incentives. Our results support the recommendation to routinely evaluate symptom validity in clinical assessments of hospital patients. The dynamics behind invalid symptom reporting need to be further elucidated.

Faking ADHD? Symptom Validity Testing and Its Relation to Self-Reported, Observer-Reported Symptoms, and Neuropsychological Measures of Attention in Adults With ADHD

Objective: To compare ADHD patients who failed a symptom validity test with those who passed the test to explore whether there are signs of negative response bias on group level. Method: In our outpatient department, 196 adults were diagnosed with ADHD using a comprehensive diagnostic strategy featuring a detailed clinical history, clinical interview, observer rating, several self-rating scales, and neuropsychological attention tests. The Amsterdam Short Term Memory Test (AKGT) was applied as a symptom validity measure. Results: Sixty-three patients (32.1%) scored below the AKGT cutoff level. The two groups did not significantly differ regarding self-report and observer ratings. Those who failed the AKGT had higher reaction time variabilities in selective, auditory and visual divided attention, and higher omission errors in sustained attention. Conclusion: We found no strong indicators for negative response bias in ADHD patients who failed a symptom validity test. New measures and approaches to detect feigned ADHD should be developed.

Swiss population-based reference data for six symptom validity tests

Symptom validity test (SVT) results should be resistant against sociodemographic variables. Healthy, cooperative respondents should be able to pass these tests. The purpose of the study was to collect reference data for a selection of SVTs (Medical Symptom Validity Test, Structured Inventory of Malingered Symptomatology, Amsterdam Short-Term Memory Test, Emotional Numbing Test, Reliable Digit Span, Maximum Span Forward). A representative population-based sample of 100 German speaking Swiss citizens from 18 to 60 years of age was investigated. Multiple regression analyses revealed that age and verbal intelligence had an effect on various SVTs, whereas sex and education did not. The rate of positive test scores ranged from 1% (Emotional Numbing Test, Structured Inventory of Malingered Symptomatology) to 4% (Maximum Span Forward). One of the pertinent questions is if such positive results in reference or normative samples represent false positives or true positives and how to deal with the problem.

Does neuropsychological test performance predict outcome of cognitive behavior therapy for Chronic Fatigue Syndrome and what is the role of underperformance?

ObjectiveA subgroup of patients with Chronic Fatigue Syndrome (CFS) has cognitive impairments, reflected by deviant neuropsychological test performance. However, abnormal test scores can also be caused by suboptimal effort. We hypothesized that worse neuropsychological test performance and underperformance were related to each other and to a smaller reduction in fatigue, functional impairments, physical limitations and higher dropout rates following cognitive behavior therapy (CBT) for CFS. MethodsData were drawn from a previous trial, in which CFS patients were randomized to two conditions; 1) guided self-instruction and additional CBT (n=84) or 2) waiting period followed by regular CBT for CFS (n=85). Underperformance was assessed using the Amsterdam Short Term Memory Test (<84). To test neuropsychological test performance, the Symbol Digit Modalities Task, a simple reaction time task and a choice reaction time task were used. Interaction effects were determined between underperformance and neuropsychological test performance on therapy outcomes. ResultsUnderperformance was associated to worse neuropsychological test performance, but there were no significant interaction effects of these two factors by therapy on fatigue severity, functional impairments and physical limitations, but there was a significant main effect of underperformance on functional impairments, physical limitations and dropout rates. ConclusionUnderperformance or neuropsychological test performance was not related to the change in fatigue, functional impairments, and physical limitations following CBT for CFS. However, underperforming patients did drop out more often. Therapists should pay attention to beliefs and behavioral or environmental factors that might maintain underperformance and increase the risk of dropout.

Swiss population-based reference data for six symptom validity tests

Symptom validity test (SVT) results should be resistant against sociodemographic variables. Healthy, cooperative respondents should be able to pass these tests. The purpose of the study was to collect reference data for a selection of SVTs (Medical Symptom Validity Test, Structured Inventory of Malingered Symptomatology, Amsterdam Short-Term Memory Test, Emotional Numbing Test, Reliable Digit Span, Maximum Span Forward). A representative population-based sample of 100 German speaking Swiss citizens from 18 to 60 years of age was investigated. Multiple regression analyses revealed that age and verbal intelligence had an effect on various SVTs, whereas sex and education did not. The rate of positive test scores ranged from 1% (Emotional Numbing Test, Structured Inventory of Malingered Symptomatology) to 4% (Maximum Span Forward). One of the pertinent questions is if such positive results in reference or normative samples represent false positives or true positives and how to deal with the problem.

Cognitive Underperformance and Symptom Over-Reporting in a Mixed Psychiatric Sample

The current study examined the prevalence of cognitive underperformance and symptom over-reporting in a mixed sample of psychiatric patients (N = 183). We employed the Amsterdam Short-Term Memory Test (ASTM) to measure cognitive underperformance and the Structured Inventory of Malingered Symptomatology (SIMS) to measure the tendency to over-report symptoms. We also administered neuropsychological tests (e.g., Concept Shifting Task; Rey's Verbal Learning Test) and the Symptom Checklist-90 (SCL-90) to the patients. A total of 34% of them failed the ASTM, the SIMS or both tests. ASTM and SIMS scores were significantly, albeit modestly, correlated with each other (r = −.22). As to the links between underperformance, over-reporting, neuropsychological tasks, and the SCL-90, the association between over-reporting on the SIMS and SCL-90 scores was the most robust one. The subsample that only failed on the ASTM performed significantly worse on a compound index of memory performance. Our findings indicate that underperformance and over-reporting are loosely coupled dimensions and that particularly over-reporting is intimately linked to heightened SCL-90 scores.

Detection of Feigned Crime-Related Amnesia: A Multi-Method Approach

Claims of crime-related amnesia appear to be common. Using a mock crime approach, the diagnostic power of seven symptom validity instruments was investigated. Sixty participants were assigned to three conditions: responding honestly; feigning crime-related amnesia; feigning amnesia with a warning not to exaggerate. High sensitivity and specificity were obtained for the Structured Inventory of Malingered Symptomatology, the Amsterdam Short-Term Memory Test, and the Morel Emotional Numbing Test. Only three warned malingerers went undetected. The results demonstrate that validated instruments exist to support forensic decision making about crime-related amnesia. Yet, warning may undermine their effectiveness, even when using a multi-method approach.

Validation of Symptom Validity Tests Using a "Child-model" of Adult Cognitive Impairments

Validation studies of symptom validity tests (SVTs) in children are uncommon. However, since children's cognitive abilities are not yet fully developed, their performance may provide additional support for the validity of these measures in adult populations. Four SVTs, the Test of Memory Malingering (TOMM), the Word Memory Test (WMT), the Amsterdam Short-Term Memory (ASTM) test, and the Word Completion Memory Test (WCMT), along with several neuropsychological instruments were administered to 48 Dutch school children aged 7-12. All children scored above the established adult cut-offs on the TOMM and the WMT. They could pass the ASTM test if their reading skills were at a level equivalent to that of 9 year olds. All children passed our criterion of a negative WCMT score. However, the WCMT does seem sensitive to the level of verbal fluency. Implications for the applicability of these SVTs in adult populations are discussed.

On the limits of effort testing: Symptom validity tests and severity of neurocognitive symptoms in nonlitigant patients

Modern symptom validity tests (SVTs) use empirical cutoffs for decision making. However, limits to the applicability of these cutoffs may arise when severe cognitive symptoms are present. The purpose of the studies presented here was to explore these limits of applicability. In Experiment 1, a group of 24 bona fide neurological patients without clinically obvious cognitive symptoms was compared to a group of 24 patients with rather severe symptoms. A comprehensive test battery was employed, which included four SVTs (the Test of Memory Malingering, TOMM, the Word Memory Test, WMT, the Bremer Symptomvalidierung, BSV, and the Amsterdam Short-Term Memory Test, ASTM). In Experiment 2, a group of 20 patients with mild Alzheimer's disease was compared to 14 healthy controls. Results of both studies showed that cognitive impairment may significantly interfere with SVT performance. Correlation analyses revealed dissimilar relationships between SVTs and neuropsychological test measures. Whereas TOMM and WMT correlated mainly with tests of declarative memory, the BSV correlated with tests of attention, and ASTM correlated with tests of working memory. Intercorrelations between symptom validity measures were relatively low. The published cutoffs of the TOMM would be suitable for estimating effort in patients with Mini-Mental State Examination scores of 24 or above. More research will be necessary to investigate how performance in SVTs is related to cognitive functioning in populations of severely impaired patients.

Symptom Information—Warning—Coaching

Abstract Coaching is a topic of utmost importance for forensic neuropsychological assessment, and symptom validity tests (SVTs) should be resistant against it. Four groups of experimental malingerers (n = 15, each) were given scenarios to feign cognitive symptoms after traumatic brain injury. Group A obtained a basic scenario. For Group B, symptom information was added. Group C received an explicit warning against exaggerating symptom presentation. Group D obtained a specific coaching which contained an introduction into principles of effort measurement. All groups were given a short neuropsychological battery including three SVTs: the Amsterdam Short-Term Memory Test (ASTM), the Medical Symptom Validity Test (MSVT), and the Word Completion Memory Test (WCMT). While a general trend for gradually better results in SVTs from Group A to Group D was observed, only in Group D were pass rates elevated for the MSVT and the WCMT. Not a single participant passed the ASTM test. Coaching appears to be more effective...

Analog validation of German-language symptom validity tests and the influence of coaching

Although symptom validity testing is an integral part of the repertory of neuropsychologists in a number of countries, this is not yet true for Germany. The German adaptations of two effort tests, the Medical Symptom Validity Test (MSVT) by Green and the Amsterdam Short-Term Memory Test (ASTM) by Schmand et al., were investigated with a German-language sample. An analog study was performed with 18 healthy experimental malingerers and 18 controls with a mean age of 25.4 years. The scenario contained detailed information about mild post-traumatic cognitive impairment, as well as an explicit warning against symptom exaggeration. In addition to MSVT and ASTM, the Trail Making Test (TMT), the Complex Figure Test (CFT), and Digit Span were performed. Half of the sample were also given Rey's 15-Item-Test (FIT). Both groups were significantly different in all effort and performance measures, with the exception of the ratio TMT-B:TMT-A. With MSVT and ASTM, correct classification of group membership was between 97 and 100%. For the ratio TMT-B:TMT-A, there was a considerable overlap in the test scores for the two groups and the sensitivity of the FIT was too low. Although the ASTM and the MSVT were identified by a number of subjects as possible effort measures, both tests obtained very good results within this analog design.

Suboptimal Performance on Neuropsychological Tests in Patients with Suspected Chronic Toxic Encephalopathy

Suboptimal performance during neuropsychological testing can seriously complicate assessment in behavioral neurotoxicology. We present data on the prevalence of suboptimal performance in a group of Dutch patients with suspected chronic toxic encephalopathy (CTE) after long-term occupational exposure to solvents. One hundred and forty-five subjects referred to one of two Dutch national assessment centers for CTE were administered the Amsterdam Short-Term Memory Test (ASTM) and the Test of Memory Malingering (TOMM), two tests specifically developed for the detection of suboptimal performance. For both tests, very cautious cut-off scores were chosen with a specificity of 99%. Results indicated that suboptimal performance appears to be a substantial problem in this group of patients with suspected CTE after long-term exposure to organic solvents. Only 54% of our subjects obtained normal scores on both tests of malingering, i.e. at or above cut-off score. The two tests seemed to measure the same concept in that nearly all the subjects with low TOMM scores also had low ASTM scores. However, a higher proportion of subjects scored below the cut-off on the ASTM than on the TOMM.

A Comparison of Three Tests to Detect Feigned Amnesia: The Effects of Feedback and the Measurement of Response Latency

Three experiments provided validation data for an English language version of the Amsterdam Short Term Memory Test (ASTM test) developed to detect feigned memory impairment. Using a simulation design, the ASTM test compared favourably with the Test of Memory Malingering (TOMM) and appeared better than a newly-devised Digit Recognition Test (DRT). Feedback on the correctness of responses had no significant effect on performance but notable trends were apparent. Simulators were significantly slower than controls on computerised versions of the ASTM test and the TOMM. Convergent findings indicate that the English language version of the ASTM test may be useful in detecting malingering.

Comment on article "Does pain confound interpretation of neuropsychological test results?"

Nicholson, Martelli and Zasler conclude their review by stating “Future studies should be informed by an understanding of the psychology of chronic pain, as well as more rigorous neuropsychological methodology”. We can only agree with this conclusion because there has been a lack of rigour in past research, much of which has simply assumed that low test scores in patients are equivalent to cognitive impairment. It is possible that chronic pain does affect cognition but we cannot be sure of this until the effects of incomplete effort on tests have been controlled properly. In this review, Nicholson, Martelli and Zasler did not quote the study in which people with chronic complaints after whiplash injuries were given an effort test, the Amsterdam Short Term Memory Test (ASTM, Schmand, 1997). Based on their ASTM results, 61% of patients were found to be exaggerating their memory impairment on formal testing. Hence, their other ability test results would be presumed to be invalid. On the other hand, the latter study was quoted by Hart et al. [5], in a review of neuropsychological functioning in chronic pain patients. These authors concluded that tests of response bias and motivation should be used in evaluating chronic pain patients, who are involved in litigation or seeking wage replacement benefits. Logically, effort tests should be used not only in clinical cases but also in all group studies of chronic pain patients. If not, the results of any study of cognition and

Amsterdam short-term memory test: A new procedure for the detection of feigned memory deficits

The validity of two malingering tests, the newly developed Amsterdam Short-Term Memory (ASTM) test and the Distraction test (Baker, Hanley, Jackson, Kimmance, & Slade, 1993) was examined in a group of patients with closed-head injury (CHI), a normal control group, and a control group with instruction to feign memory deficits. Both control groups consisted of first-degree relatives of the patients. The ASTM test is a forced-choice verbal memory test, based on the technique of symptom validity testing. Stimulus material was chosen from category norms, and chance level is not transparent. The CHI and normal control groups scored near ceiling on the ASTM test, whereas the feigned deficit group scored significantly worse. The ASTM test classified all subjects correctly. Contrary to expectation, the Distraction test appeared to be invalid. The score profiles of the CHI and feigning groups on conventional memory and concentration tests were indistinguishable from each other. Thus, the ASTM test may be very useful for the detection of malingering and other kinds of less than optimal performance. The test may readily be constructed in any language for which category norms are available.

A phenomenological test of the validity of the deficit syndrome

Although symptom validity testing is an integral part of the repertory of neuropsychologists in a number of countries, this is not yet true for Germany. The German adaptations of two effort tests, the Medical Symptom Validity Test (MSVT) by Green and the Amsterdam Short-Term Memory Test (ASTM) by Schmand et al., were investigated with a German-language sample. An analog study was performed with 18 healthy experimental malingerers and 18 controls with a mean age of 25.4 years. The scenario contained detailed information about mild post-traumatic cognitive impairment, as well as an explicit warning against symptom exaggeration. In addition to MSVT and ASTM, the Trail Making Test (TMT), the Complex Figure Test (CFT), and Digit Span were performed. Half of the sample were also given Rey's 15-Item-Test (FIT). Both groups were significantly different in all effort and performance measures, with the exception of the ratio TMT-B:TMT-A. With MSVT and ASTM, correct classification of group membership was between 97 and 100%. For the ratio TMT-B:TMT-A, there was a considerable overlap in the test scores for the two groups and the sensitivity of the FIT was too low. Although the ASTM and the MSVT were identified by a number of subjects as possible effort measures, both tests obtained very good results within this analog design.