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AbstractDetecting malingered neurocognitive dysfunction is a major issue in forensic context, particularly in legal proceeding/insurance assessment after a traumatic brain injury (TBI), condition frequently associated with persistent cognitive impairments that may potentially be related to malingering. Consequently, research has devoted considerable efforts on developing tools to verify symptoms authenticity. This study compared two freestanding performance validity tests (PVTs) (Amsterdam Short-Term Memory Test—ASTM; Word Completion Memory Test—WCMT) and five embedded PVTs (Rey Complex Figure Test—RCFT—Copy and Recall trials; Reliable Digit Span—RDS; Rey Auditory Verbal Learning Test—RAVLT—Recognition and Total Learning trials) in a sample of 120 participants, including 15 patients with TBI (Mage = 44.40), 52 experimental simulators (Mage = 29.52) and 53 control (Mage = 29.77). Group performance was analyzed to assess tests’ discriminatory power, and Receiver Operating Characteristic (ROC) curves were used to examine tools’ sensitivity and specificity. Results indicated that experimental simulators performance on the ASTM, WCMT, and RAVLT differed significantly from TBI patients and controls. The RDS and RCFT did not discriminate experimental simulators from TBI group. ROC curves analysis reveals that the most accurate tests in this battery for detecting malingering were the ASTM and the RAVLT-Total Learning score. This study offers implications for identifying malingering in medico-legal settings, underscoring the importance of incorporating PVTs into clinical practice. [ABSTRACT FROM AUTHOR]

The study examined the effect of preparation time and financial incentives on healthy adults' ability to simulate traumatic brain injury (TBI) during neuropsychological evaluation. A retrospective comparison of two TBI simulator group designs: a traditional design employing a single-session of standard coaching immediately before participation (SIM-SC; n = 46) and a novel design that provided financial incentive and preparation time (SIM-IP; n = 49). Both groups completed an ecologically valid neuropsychological test battery that included widely-used cognitive tests and five common performance validity tests (PVTs). Compared to SIM-SC, SIM-IP performed significantly worse and had higher rates of impairment on tests of processing speed and executive functioning (Trails A and B). SIM-IP were more likely than SIM-SC to avoid detection on one of the PVTs and performed somewhat better on three of the PVTs, but the effects were small and non-significant. SIM-IP did not demonstrate significantly higher rates of successful simulation (i.e., performing impaired on cognitive tests with <2 PVT failures). Overall, the rate of the successful simulation was ∼40% with a liberal criterion, requiring cognitive impairment defined as performance >1 SD below the normative mean. At a more rigorous criterion defining impairment (>1.5 SD below the normative mean), successful simulation approached 35%. Incentive and preparation time appear to add limited incremental effect over traditional, single-session coaching analog studies of TBI simulation. Moreover, these design modifications did not translate to meaningfully higher rates of successful simulation and avoidance of detection by PVTs. [ABSTRACT FROM AUTHOR]

Objectives: To determine base rates of invalid performance on the Test of Memory Malingering (TOMM) in patients with traumatic brain injury (TBI) undertaking rehabilitation who were referred for clinical assessment, and the factors contributing to TOMM failure. Methods: Retrospective file review of consecutive TBI referrals for neuropsychological assessment over seven years. TOMM failure was conventionally defined as performance <45/50 on Trial 2 or Retention Trial. Demographic, injury, financial compensation, occupational, and medical variables were collected. Results: Four hundred and ninety one TBI cases (Median age = 40 years [IQR = 26–52], 79% male, 82% severe TBI) were identified. Overall, 48 cases (9.78%) failed the TOMM. Logistic regression analyses revealed that use of an interpreter during the assessment (adjusted odds ratio [aOR] = 8.25, 95%CI = 3.96–17.18), outpatient setting (aOR = 4.80, 95%CI = 1.87–12.31) and post-injury psychological distress (aOR = 2.77, 95%CI = 1.35–5.70) were significant multivariate predictors of TOMM failure. The TOMM failure rate for interpreter cases was 49% (21/43) in the outpatient setting vs. 7% (2/30) in the inpatient setting. By comparison, 9% (21/230) of non-interpreter outpatient cases failed the TOMM vs. 2% (4/188) of inpatient cases. Conclusions: TOMM failure very rarely occurs in clinical assessment of TBI patients in the inpatient rehabilitation setting. It is more common in the outpatient setting, particularly in non-English-speaking people requiring an interpreter. The findings reinforce the importance of routinely administering stand-alone performance validity tests in assessments of clinical TBI populations, particularly in outpatient settings, to ensure that neuropsychological test results can be interpreted with a high degree of confidence. [ABSTRACT FROM AUTHOR]

Objective: The addition of Sequencing to WAIS-IV Digit Span (DS) brought about new Reliable Digit Span (RDS) indices and an Age-Corrected Scaled Score that includes Sequencing trials. Reports have indicated that these new performance validity tests (PVTs) are superior to the traditional RDS; however, comparisons in the context of known neurocognitive impairment are sparse. This study compared DS-derived PVT classification accuracies in a design that included adults with verified TBI. Methods: Participants included 64 adults with moderate-to-severe TBI (TBI), 51 healthy adults coached to simulate TBI (SIM), and 78 healthy comparisons (HC). Participants completed the WAIS-IV DS subtest in the context of a larger test battery. Results: Kruskal–Wallis tests indicated that all DS indices differed significantly across groups. Post hoc contrasts revealed that only RDS Forward and the traditional RDS differed significantly between SIM and TBI. ROC analyses indicated that RDS variables were comparable predictors of SIM vs. HC; however, the traditional RDS showed the highest sensitivity when approximating 90% specificity for SIM vs. TBI. A greater percentage of TBI scored RDS Sequencing < 1 compared to SIM and HC. Conclusion: In the context of moderate-to-severe TBI, the DS-derived PVTs showed comparable discriminability. However, the Greiffenstein et al. traditional RDS demonstrated the best classification accuracy with respect to specificity/sensitivity balance. This relative superiority may reflect that individuals with verified TBI are more likely to perseverate on prior instructions during DS Sequencing. Findings highlight the importance of including individuals with verified TBI when evaluating and developing PVTs. [ABSTRACT FROM AUTHOR]

Objective: To determine clinically meaningful subgroups of persons with traumatic brain injury (TBI) who have failed performance validity testing. Method: Study participants were selected from a cohort of 674 participants with definitive medical evidence of TBI. Participants were those who failed performance validity testing (the Word Memory Test, using the standard cutoffs). Participants were administered cognitive tests and self-report questionnaires. Test and questionnaire results were summarized as 12 dimension scores. Cluster analysis using the k-means method was performed. Results: Cluster analysis for the 143 retained participants indicated three subgroups. These subgroups differed on patterns of scores. Subgroup 1 was impaired for memory and had no excessive complaints. Subgroup 2 had impaired memory and processing speed as well as concern regarding cognition function. Subgroup 3 showed impairment on all cognitive tests and excess complaints in multiple areas. Conclusions: These results provide a preliminary basis for improved understanding of poor performance validity. [ABSTRACT FROM AUTHOR]