Performance and Symptom Validity Assessment in Patients with Apathy and Cognitive Impairment.

OBJECTIVE: Performance and symptom validity tests (PVTs and SVTs) measure the credibility of the assessment results. Cognitive impairment and apathy potentially interfere with validity test performance and may thus lead to an incorrect (i.e., false-positive) classification of the patient's scores as non-credible. The study aimed at examining the false-positive rate of three validity tests in patients with cognitive impairment and apathy. METHODS: A cross-sectional, comparative study was performed in 56 patients with dementia, 41 patients with mild cognitive impairment, and 41 patients with Parkinson's disease. Two PVTs - the Test of Memory Malingering (TOMM) and the Dot Counting Test (DCT) - and one SVT - the Structured Inventory of Malingered Symptomatology (SIMS) - were administered. Apathy was measured with the Apathy Evaluation Scale, and severity of cognitive impairment with the Mini Mental State Examination. RESULTS: The failure rate was 13.7% for the TOMM, 23.8% for the DCT, and 12.5% for the SIMS. Of the patients with data on all three tests (n = 105), 13.5% failed one test, 2.9% failed two tests, and none failed all three. Failing the PVTs was associated with cognitive impairment, but not with apathy. Failing the SVT was related to apathy, but not to cognitive impairment. CONCLUSIONS: In patients with cognitive impairment or apathy, failing one validity test is not uncommon. Validity tests are differentially sensitive to cognitive impairment and apathy. However, the rule that at least two validity tests should be failed to identify non-credibility seemed to ensure a high percentage of correct classification of credibility.

Effort and neuropsychological performance in HIV-infected individuals on stable combination antiretroviral therapy.

The expression of cognitive symptoms associated with HIV varies over time and across individuals. This pattern may reflect transient contextual factors, including the degree of effort exerted by individuals undergoing cognitive testing. The present study examined whether effort corresponds to the expression of persistent HIV-related cognitive impairment among individuals receiving combination antiretroviral therapy (cART). HIV+ individuals (n = 111) averaged 48.2 (14.9) years of age and 13.0 (2.7) years of education and HIV- individuals (n = 92) averaged 34.9 (17.2) years of age and 13.5 (1.9) years of education. Participants completed a neuropsychological battery and a clinically validated measure of effort (Test of Memory Malingering, trial 1). Results revealed that the vast majority of HIV+ (85%) and HIV- (89%) individuals performed above published guidelines for adequate effort. Furthermore, the expression of cognitive impairment in HIV was not related to effort performance. The results were unchanged when examining HIV+ individuals with and without viral suppression. Finally, disability and disability-seeking status, and a proxy measure of apathy did not correspond to effort levels in HIV+ individuals. These findings suggest that variability in the expression of cognitive impairment in the cART era is unlikely to represent overt effort failures or other confounds unrelated to the disease. Persistent cognitive impairment in HIV likely represents historical and/or ongoing disease mechanisms despite otherwise successful treatment.

A single error is one too many: Examining alternative cutoffs on Trial 2 of the TOMM.

OBJECTIVE: This study investigated the potential of alternative, more liberal cutoffs on Trial 2 of the Test of Memory Malingering (TOMM) to improve classification accuracy relative to the standard cutoffs (≤44). METHOD: The sample consisted of 152 patients (49.3% male) with psychiatric conditions (PSY) and traumatic brain injury (TBI) referred for neuropsychological assessment in a medico-legal setting (MAge = 44.4, MEducation = 11.9 years). Classification accuracy for various TOMM Trial 2 cutoffs was computed against three criterion measures. RESULTS: Patients with TBI failed TOMM Trial 2 cutoffs at higher rates than patients with PSY. Trial 2 ≤49 achieved acceptable combinations of sensitivity (0.38-0.67) and specificity (0.89-0.96) in all but one comparison group. Trial 2 ≤48 improved specificity (0.94-0.98) with minimal loss in sensitivity. The standard cutoff (≤44) disproportionally traded sensitivity (0.15-0.50) for specificity (0.96-1.00). CONCLUSIONS: One error on TOMM Trial 2 constitutes sufficient evidence to question the credibility of a response set. However, the confidence in classifying a score as invalid continues to increase with each additional error. Even at the most liberal conceivable cutoff (≤49), the TOMM detected only about half of the patients who failed other criterion measures. Therefore, it should never be used in isolation to determine performance validity.

Test of memory Malingering 2nd Edition: Normative data from cognitively intact adults living in Spain.

This study evaluated the universality of the TOMM 2 and provided a reference sample of cognitively intact adults living in Spain whose native language was Spanish. A total of 203 adults completed the TOMM 2 from June 2019 to January 2020. When using the original TOMM cutoff scores derived from English speakers, all participants scored in a range that would suggest that they passed the TOMM. When using a cut score less than 40 on Trial 1, only one participant in this study would be mistakenly classified as providing an invalid performance. Spanish-speaking adults in Spain from this study achieved a perfect score on Trial 1 at a rate more than double that of English-speaking individuals on the original TOMM. At the item level, all but one item met the minimum standard for performance validity; this item fell only marginally below the standard at 89%. This study found a very low failure rate for the TOMM 2, suggesting that the second edition has at least as high specificity as the original in Spanish adults.

Performance validity in a presurgical epilepsy population.

Objective: This study examined the performance validity test (PVT) pass/fail rate in a sample of presurgical epilepsy candidates; assessed whether performance validity was associated with reduced performance across cognitive domains; investigated the relationship between performance validity and self-report mood questionnaires; and assessed whether PVT performance was associated with demographic or clinical factors (i.e. sex, race/ethnicity, age, years of education, reported history of special education, seizure longevity, and number of anti-seizure medications). Methods: One hundred and eighty-three presurgical epilepsy candidates were examined. Each patient's assessment battery included a stand-alone performance validity measure and two embedded validity measures. Results: PVT failure rate in this sample (10%) was associated with reduced performance on all neurocognitive measures: Full Scale IQ (FSIQ; r = -0.26), CVLT-II Total Learning (r = -0.36) and Long Delay Free Recall (LDFR; r = -0.38), BVMT-R Delayed Recall (r = -0.28), and Wisconsin Card Sorting Test (Categories Completed; r = -0.32). In addition, PVT failure rate was associated with elevated scores on the Beck Anxiety Inventory (r = .22) but not on the Beck Depression Inventory (BDI-II; r = .14). Correlations that were significant at the α = 0.05 level maintained significance following post hoc Bonferroni correction. The valid and invalid groups did not differ significantly in sex, race/ethnicity, age, years of education, reported history of special education, seizure longevity, and number of anti-seizure medications. Conclusions: Results from this study suggest that PVT performance was not impacted by demographic or clinical factors and therefore may be a reliable indicator of performance validity in a presurgical epilepsy sample.

The TOMM1 discrepancy index (TDI): A new performance validity test (PVT) that differentiates between invalid cognitive testing and those diagnosed with dementia.

There is a need to develop performance validity tests (PVTs) that accurately identify those with severe cognitive decline but also remain sensitive to those suspected of invalid cognitive testing. The TOMM1 Discrepancy Index (TDI) attempts to address both of these issues. Veterans diagnosed with dementia (n = 251) were administered TOMM1 and the MSVT in order to develop the TDI (TOMM1 percent correct minus MSVT Free Recall percent correct). Cut offs based on the dementia sample were then used to identify those in the non-dementia sample (n = 1,226) suspected of invalid test performance (n = 401). Combining TOMM1 and the TDI in the dementia sample greatly reduced the false positive rate (specificity = 0.97) at a cut off of 28 points or less on the TDI. Those suspected of invalid testing were identified at much higher rates (sensitivity = 0.75) compared to the MSVT genuine memory impairment profile (GMIP, sensitivity = 0.49). By utilizing a neurologically plausible pattern of scores across two PVTs, the TDI correctly classified those with dementia and identified a large percentage with invalid test performance. PVTs utilizing a complex pattern of performance may help reduce one's ability to fabricate cognitive deficits.

Validity assessment in Eastern Europe: cross-validation of the Dot Counting Test and MODEMM against the TOMM-1 and Rey-15 in a Romanian mixed clinical sample.

OBJECTIVE: This study investigated performance validity in the understudied Romanian clinical population by exploring classification accuracies of the Dot Counting Test (DCT) and the first Romanian performance validity test (PVT) (Memory of Objects and Digits and Evaluation of Memory Malingering/MODEMM) in a heterogeneous clinical sample. METHODS: We evaluated 54 outpatients (26 females; MAge = 62.02; SDAge = 12.3; MEducation = 2.41, SDEducation = 2.82) with the Test of Memory Malingering 1 (TOMM-1), Rey Fifteen Items Test (Rey-15) (free recall and recognition trials), DCT, MODEMM, and MMSE/MoCA as part of their neuropsychological assessment. Accuracy parameters and base failure rates were computed for the DCT and MODEMM indicators against the TOMM-1 and Rey-15. Two patient groups were constructed according to psychometrically defined credible/noncredible performance (i.e., pass/fail both TOMM-1 and Rey-15). RESULTS: Similar to other cultures, a cutoff of ≥18 on the DCT E score produced the best combination between sensitivity (0.50-0.57) and specificity (≥0.90). MODEMM indicators based on recognition accuracy, inconsistencies, and inclusion false positives generated 0.75-0.86 sensitivities at ≥0.90 specificities. Multivariable models of MODEMM indicators reached perfect sensitivities at ≥0.90 specificities against two PVTs. Patients who failed the TOMM-1 and Rey-15 were significantly more likely to fail the DCT and MODEMM than patients who passed both PVTs. CONCLUSIONS: Our results offer proof of concept for the DCT's cross-cultural validity and the applicability of the MODEMM on Romanian clinical examinees, further recommending the use of heterogeneous validity indicators in clinical assessments.

The rate of psychiatric disorders in veterans undergoing intensive EEG monitoring is associated with symptom and performance invalidity.

To determine if the number of participants with psychiatric disorders increased in association with failures on symptom validity tests (SVTs) and a performance validity test (PVT) in Veterans admitted for evaluation of possible seizures.The 254 participants were Veterans undergoing inpatient video-EEG monitoring for the diagnosis of possible seizures. DSM-IV psychiatric disorders were diagnosed with the SCID IV. Symptom exaggeration was assessed with the MMPI-2-RF and performance validity with the TOMM.On the MMPI-2-RF, 27.6%-32.7% showed symptom exaggeration. Participants who exaggerated on the MMPI-2-RF were more often diagnosed with psychiatric disorders. The TOMM was failed by 15.4% of the sample. Participants who failed the TOMM were more often diagnosed with an Axis I disorder but not with a personality disorder. The MMPI-2-RF was invalid in more cases than the TOMM, but 7.9% of the sample generated a valid MMPI-2-RF and an invalid TOMM.The correlational design does not allow conclusions about cause and effect. The invalid groups may have had a higher rate of psychopathology. The number of participants with psychiatric disorders increased in association with symptom exaggeration and performance invalidity. Symptom exaggeration was more frequent than performance invalidity, but the TOMM made a unique contribution to identification of invalidity. The routine clinical use of SVTs and PVTs is supported. The results also suggest the need for caution in diagnosing psychiatric disorders when there is symptom exaggeration or performance invalidity, because diagnostic validity is dependent on the accuracy of symptom reporting.

When 10 is enough: Errors on the first 10 items of the Test of Memory Malingering (TOMMe10) and administration time predict freestanding performance validity tests (PVTs) and underperformance on memory measures.

It is critical that we develop more efficient performance validity tests (PVTs). A shorter version of the Test of Memory Malingering (TOMM) that utilizes errors on the first 10 items (TOMMe10) has shown promise as a freestanding PVT. Retrospective review included 397 consecutive veterans administered TOMM trial 1 (TOMM1), the Medical Symptom Validity Test (MSVT), and the Brief Visuospatial Memory Test-Revised (BVMT-R). TOMMe10 accuracy and administration time were used to predict performance on freestanding PVTs (TOMM1, MSVT). The impact of failing TOMMe10 (2 or more errors) on independent memory measures was also explored. TOMMe10 was a robust predictor of TOMM1 (area under the curve [AUC] = 0.97) and MSVT (AUC = 0.88) with sensitivities = 0.76 to 0.89 and specificities = 0.89 to 0.96. Administration time predicted PVT performance but did not improve accuracy compared to TOMMe10 alone. Failing TOMMe10 was associated with clinically and statistically significant declines on the BVMT-R and MSVT Paired Associates and Free Recall memory tests (d = -0.32 to -1.31). Consistent with prior research, TOMMe10 at 2 or more errors was highly accurate in predicting performance on other well-validated freestanding PVTs. Failing just 1 freestanding PVT (TOMMe10) significantly impacted memory measures and likely reflects invalid test performance.

New cut-score to improve performance of the Memory Validity Profile (MVP) in heterogenous clinical populations.

The Memory Validity Profile (MVP) is a standalone performance validity test developed specifically for use with children. Prior research has demonstrated the MVP's strength in its ease of administration to children with a wide range of intellectual abilities. However, it has been found to lack sensitivity in detecting noncredible performance in select clinical populations using published cutoffs. The current study examines the MVP's performance in a diagnostically heterogeneous clinical sample and proposes a new cutoff for optimization of sensitivity and specificity. Archival clinical data were examined from 96 participants referred for a comprehensive neuropsychological evaluation (ages 6-18). Receiver operating characteristic analysis was used to assess the discriminative ability of MVP in detecting cases of noncredible performance defined as failures on both the Test of Memory Malingering and Reliable Digit Span. Using published cutoffs, the MVP demonstrated perfect specificity (100%) but suboptimal sensitivity (33.3%). Receiver operating characteristic analysis revealed strong discrimination using MVP Total score (AUC = 0.891 (p < 0.001)) and a MVP Total cut-score of ≤30 resulted in optimal sensitivity (89%) and specificity (63%). Our findings provide additional evidence that published MVP cutoffs may be too lenient to adequately capture instances of noncredible performance and indicate an MVP Total score cutoff of ≤30 may be more appropriate for use with heterogeneous clinical populations.

Evaluation of the classification accuracy of multiple performance validity tests in a mixed clinical sample.

The Test of Memory Malingering (TOMM) and Word Memory Test (WMT) are among the most well-known performance validity tests (PVTs) and regarded as gold standard measures. Due to the many factors that impact PVT selection, it is imperative that clinicians make informed clinical decisions with respect to additional or alternative PVTs that demonstrate similar classification accuracy as these well-validated measures. The present archival study evaluated the agreement/classification accuracy of a large battery consisting of multiple other freestanding/embedded PVTs in a mixed clinical sample of 126 veterans. We examined failure rates for all standalone/embedded PVTs using established cut-scores and calculated pass/fail agreement rates and diagnostic odds ratios for various combinations of PVTs using the TOMM and WMT as criterion measures. TOMM and WMT demonstrated the best agreement, followed by Word Choice Test (WCT). The Rey Fifteen Item Test had an excessive number of false-negative errors and reduced classification accuracy. The Digit Span age-corrected scaled score (DS-ACSS) had highest agreement. Findings lend further support to the use of a combination of embedded and standalone PVTs in identifying suboptimal performance. Results provide data to enhance clinical decision making for neuropsychologists who implement combinations of PVTs in a larger clinical battery.

Cross-validation of the Invalid Forgetting Frequency Index (IFFI) from the Test of Memory Malingering.

OBJECTIVE: To increase sensitivity of the Test of Memory Malingering (TOMM), adjustments have been proposed, including adding consistency indices. The Invalid Forgetting Frequency Index (IFFI) is the most recently developed consistency index. While strong classification accuracy rates were originally reported, it currently lacks cross-validation. METHOD: A sample of 184 outpatients was utilized. Valid performers passed all criterion performance validity tests (PVTs) and invalid performers failed two or more PVTs. Classification accuracy statistics were calculated. RESULTS: AUC for the IFFI was 0.80, demonstrating adequate discrimination between valid and invalid groups. A score of 3 or more inconsistent responses resulted in sensitivity and specificity rates of 63% and 92%, respectively. CONCLUSIONS: This is the first article to cross-validate the IFFI. In both the original IFFI study and the current study, the same cut-off was found to maintain at least 90% specificity while producing higher sensitivity rates than those achieved by traditional TOMM indices.

Impact of criterion measures on the classification accuracy of TOMM-1.

This study was designed to examine the effect of various criterion measures on the classification accuracy of Trial 1 of the Test of Memory Malingering (TOMM-1), a free-standing performance validity test (PVT). Archival data were collected from a case sequence of 91 (M Age = 42.2 years; M Education = 12.7) patients clinically referred for neuropsychological assessment. Trials 2 and Retention of the TOMM, the Word Choice Test, and three validity composites were used as criterion PVTs. Classification accuracy varied systematically as a function of criterion PVT. TOMM-1 ≤ 43 emerged as the optimal cutoff, resulting in a wide range of sensitivity (.47-1.00), with perfect overall specificity. Failing the TOMM-1 was unrelated to age, education or gender, but was associated with elevated self-reported depression. Results support the utility of TOMM-1 as an independent, free-standing, single-trial PVT. Consistent with previous reports, the choice of criterion measure influences parameter estimates of the PVT being calibrated. The methodological implications of modality specificity to PVT research and clinical/forensic practice should be considered when evaluating cutoffs or interpreting scores in the failing range.

The Multi-Level Pattern Memory Test (MPMT): Initial Validation of a Novel Performance Validity Test.

Performance validity tests (PVTs) are used for the detection of noncredible performance in neuropsychological assessments. The aim of the study was to assess the efficacy (i.e., discrimination capacity) of a novel PVT, the Multi-Level Pattern Memory Test (MPMT). It includes stages that allow profile analysis (i.e., detecting noncredible performance based on an analysis of participants' performance across stages) and minimizes the likelihood that it would be perceived as a PVT by examinees. In addition, it utilizes nonverbal stimuli and is therefore more likely to be cross-culturally valid. In Experiment 1, participants that were instructed to simulate cognitive impairment performed less accurately than honest controls in the MPMT (n = 67). Importantly, the MPMT has shown an adequate discrimination capacity, though somewhat lower than an established PVT (i.e., Test of Memory Malingering-TOMM). Experiment 2 (n = 77) validated the findings of the first experiment while also indicating a dissociation between the simulators' objective performance and their perceived cognitive load while performing the MPMT. The MPMT and the profile analysis based on its outcome measures show initial promise in detecting noncredible performance. It may, therefore, increase the range of available PVTs at the disposal of clinicians, though further validation in clinical settings is mandated. The fact that it is an open-source software will hopefully also encourage the development of research programs aimed at clarifying the cognitive processes involved in noncredible performance and the impact of PVT characteristics on clinical utility.

Early Cutoff Criteria for Strong Performance on the Test of Memory Malingering.

OBJECTIVE: The Test of Memory Malingering (TOMM) is widely used to assess performance validity. To improve efficiency, we investigated whether abbreviated administration (i.e., only the first 25 items of Trial 1 [T1]) is possible when effort is very strong (≥49/50 on T1 or T2). METHOD: We collected TOMM scores of 501 consecutive adult patients ranging in cognitive status who underwent standard neuropsychological evaluation at Mayo Clinic, Rochester, MN. RESULTS: Receiver Operating Characteristic (ROC) analysis showed excellent area under the curve (AUC) (0.94; CI95% [0.92, 0.97]) and a cutoff of 25/25 had 100% specificity for identifying strong performance. Of the 224 patients who obtained a perfect score on the first 25 items, 197 (88%) obtained ≥49 on T1 and the remaining patients (n = 27) obtained ≥49 on T2. CONCLUSION: A perfect score on the first 25 items of the TOMM predicted overall strong performance 100% of the time, supporting abbreviated administration in select cases in a general outpatient clinical setting.

A systematic review and meta-analysis of the Test of Memory Malingering in adults: Two decades of deception detection.

Objective: The present study, adhering to Preferred Reporting Items for Systematic review and Meta-Analyses (PRISMA) guidelines, is the first systematic review and meta-analysis of the Test of Memory Malingering (TOMM) to examine traditional and alternative cutoffs across Trial 1, Trial 2, and Retention.Method: Search criteria identified 539 articles published from 1997 to 2017. After application of selection criteria, 60 articles were retained for meta-analysis. Classification accuracy statistics were calculated using fixed- and random-effects models.Results: For Trial 1, a cutoff of <42 was found to result in the highest sensitivity value (0.59-0.70) when maintaining specificity at ≥0.90. Traditional cutoffs for Trial 2 and Retention were highly specific (0.96-0.98) and moderately sensitive (0.46-0.56) when considering all available studies and only neurocognitive/psychiatric samples classified by known-groups design. For both trials, a modified cutoff of <49 allowed for improved sensitivity (0.59-0.70) while maintaining adequate specificity (0.91-0.97). A supplementary review revealed that traditional TOMM cutoffs produced >0.90 specificity across most samples of examinees for whom English is not the primary language, but well-below acceptable levels in individuals with dementia.Conclusions: The TOMM is highly specific when interpreted per traditional cutoffs. In individuals not suspected of significant impairment, findings indicate that a less conservative TOMM Trial 2 or Retention cutoff of <49 can be interpreted as invalid, especially in settings associated with higher base rates of invalidity and, thus, higher positive predictive power. A cutoff of <42 on Trial 1 can also be interpreted as invalid in most settings.

Effects of Korsakoff Amnesia on performance and symptom validity testing.

Performance validity tests (PVTs) and Symptom validity tests (SVTs) are developed to identify people that present false or exaggerated symptoms. Although a key factor of both types of tests includes relative insensitivity to cognitive disorders, the direct effects of amnesia have been poorly studied. Therefore, a sample of 20 patients diagnosed with Korsakoff Amnesia (KA) through neuropsychological assessment and 20 healthy comparisons (HC) were administered the Test of Memory Malingering (TOMM), the Structured Inventory of Malingered Symptomatology (SIMS), and the newly developed Visual Association Test - Extended (VAT-E). Our results show that KA patients scored systematically lower on the TOMM and VAT-E, while performance on the SIMS was comparable with healthy comparisons. Some KA patients were regarded as underperformers based on the TOMM and VAT-E, suggesting limitations in applying these instruments in severe amnesia. There was a strong interdependence of PVTs in logistic regression. We conclude that the TOMM and VAT-E are not fully robust against severe memory disorders and show a serious risk of false positives. Complete neuropsychological profile analysis is needed, and PVTs should be interpreted with caution in patients with suspected amnesia.

A Systematic Review and Meta-Analysis of the Utility of the Test of Memory Malingering in Pediatric Examinees.

OBJECTIVE: This is the first systematic review and meta-analysis of the Test of Memory Malingering (TOMM) in pediatric examinees. It adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. METHOD: A systematic literature search was conducted using PsycINFO and PubMed, reviewing articles from January 1997 to July 2019. Books providing data on pediatric validity testing were also reviewed for references to relevant articles. Eligibility criteria included publication in a peer-reviewed journal, utilizing a pediatric sample, providing sufficient data to calculate specificity and/or sensitivity, and providing a means for evaluating validity status external to the TOMM. After selection criteria were applied, 9 articles remained for meta-analysis. Samples included clinical patients and healthy children recruited for research purposes; ages ranged from 5 to 18. Fixed and random effects models were used to calculate classification accuracy statistics. RESULTS: Traditional adult-derived cutoffs for Trial 2 and Retention were highly specific (0.96-0.99) in pediatric examinees for both clinical and research samples. Sensitivity was relatively strong (0.68-0.70), although only two studies reported sensitivity rates. A supplemental review of the literature corroborated these findings, revealing that traditional adult-based TOMM cutoffs are supported in most pediatric settings. However, limited research exists on the impact of very young age, extremely low cognitive functioning, and varying clinical diagnoses. CONCLUSIONS: The TOMM, at traditional adult cutoffs, has strong specificity as a performance validity test in pediatric neuropsychological evaluations. This meta-analysis found that specificity values in children are comparable to those of adults. Areas for further research are discussed.

Stratified performance on the Test of Memory Malingering (TOMM) is associated with differential responding on the Personality Assessment Inventory (PAI).

Introduction: This study evaluated symptom endorsement patterns in participants at various stratified performance levels on the Test of Memory Malingering (TOMM). It was hypothesized that the lowest stratum (chance performance and below) would have the most pathological (i.e., elevated item endorsement) responding on the Personality Assessment Inventory (PAI) validity and clinical scales. This study was primarily a replication of previous work with emphasis on the PAI scales and consideration of varying degrees of performance on TOMM Trial 2.Methods: Participants were 760 (54% female, 85.4% Caucasian, mean age = 42.01 (SD = 15.89), mean education = 13.55 (SD = 2.35)) consecutively referred neuropsychological outpatients who completed the TOMM and PAI. Participants were placed in one of 5 stratified TOMM Trial 2 performance level groups (High Pass, Low Pass, High Fail, Low Fail, and Chance). No significant differences were found between the demographic variables except for referral source, which was overrepresented in the Chance group relative to the other groups.Results: Due to the highly skewed nature of TOMM Trial 2, Spearman rank order correlations were calculated for the 5 stratified levels of TOMM performance and all the main PAI scales. The NIM, SOM, DEP, ANX, SCZ and SUI scales had significant correlations, so a series of One-way ANOVAs were calculated to examine these scales at different TOMM stratified performance levels. Results indicated that the Chance group had the highest level of responding on all scales, with NIM, SOM, DEP, SCZ and SUI having mean elevations above the clinical cutoff (T = 70).Conclusions: Results were consistent with previous pass-fail PVT research, but extended earlier research to provide evidence that Chance performance group had more pathological PAI responding. The results provide preliminary evidence to support the notion that patients who fail PVTs at different levels do not have the same characteristics.

Introduction to special issue on effort testing in children and adolescents.

This manuscript reviews the past history of effort testing in children and adolescents. Results in children and adults are briefly described on tests such as the Word Memory Test (WMT), the Medical Symptom Validity Test (MSVT), the Nonverbal Medical Symptom Validity Test (NV-MSVT) and Test of Memory Malingering (TOMM). Articles in the Special Issue are also briefly described.