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Objectives of the current study were to cross validate the Pain Disability Index (PDI) as a measure of symptom validity in a large sample of mild traumatic brain injury (MTBI) litigants with persistent post-concussive pain complaints, and investigate the effects of performance and symptom validity testing on PDI scores. Participants included 91 adults who underwent a comprehensive neuropsychological examination. Criterion groups were formed based upon their performance on stand-alone measures of cognitive performance validity (PVT), and the MMPI-2-RF Symptom Validity Scale (FBS-r) as a measure of symptom validity (SVT). Participants who failed PVT and SVT scored significantly higher on the PDI compared to participants who passed both. Failing both was associated with a large effect size. Failing PVT, but passing SVT, was associated with a medium effect on PDI scores, while passing PVT, but failing SVT demonstrated a small effect. A PDI cutscore of 49 was associated with.90 specificity and.47 sensitivity. The PDI demonstrates external validity as a self-report measure of symptom validity in MTBI litigants with persistent post-concussive pain complaints. A dose response relationship exists between PVT, SVT and PDI scores. Forensic examiners should include both PVT and SVT to optimize clinical decision making when evaluating MTBI litigants with complaints of pain-related disability years post-incident. [ABSTRACT FROM AUTHOR]

This study examined the efficacy of CVLT-3 response bias (i.e., parametric and nonparametric response bias) indices in differentiating between a clinical sample with traumatic brain injury and a litigating sample with poor performance validity. Participants included 106 individuals, divided into two groups: clinical group with TBI (n = 56) and a litigating group who demonstrated inadequate performance validity (n = 50), as measured by failure on at least two performance validity tests. Archival CVLT-II data was rescored utilizing the CVLT-3 scoring and normative data. Receiver operator characteristic (ROC) curve analysis was used to evaluate the diagnostic discriminability of the two response bias indices. Both parametric and nonparametric bias indices showed acceptable levels of diagnostic discrimination: AUC =.791 for parametric response bias and AUC =.753 for nonparametric response bias. Parametric response bias' discrimination was statistically superior to the nonparametric responses bias' discrimination. The CVLT-3 response bias score demonstrated good sensitivity and specificity when differentiating between individuals in a clinical sample with TBI and individuals in litigation who demonstrated inadequate performance validity. [ABSTRACT FROM AUTHOR]

Response distortions in the reporting of postconcussion symptoms can occur for many reasons. The Rivermead Post-concussion Symptoms Questionnaire (RPQ) was recently modified to include an embedded symptom validity indicator to test for atypical symptoms. The present study used a simulation design to investigate the psychometric properties of the modified RPQ (mRPQ). 298 adult volunteers were randomised into three groups: honest responding (Controls, C) who reported actual, current symptoms; mild traumatic brain injury (mTBI) simulators (MS) who role played being injured, and; biased mTBI simulators (BMS) who role played being injured and were asked to bias (exaggerate) their response. The MS and BMS participants received instructions to support the simulation. All participants completed the mRPQ and a modified Neurobehavioral Symptom Inventory (mNSI). A 2 × 3 mixed ANOVA with one within-group variable (Symptom type: Standard or Atypical) and one between-group variable (Instruction type: C, MS, BMS) found a significant two-way interaction (p <.05, ηp2 =.08). The BMS group had score elevations for both standard and atypical postconcussion symptoms; therefore, both symptom types should be considered when evaluating for biased responding. The mRPQ has promising psychometric properties and should be further developed. [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 We sought to determine the accuracy of embedded performance measures for the D–KEFS Color Word Interference Test that were recently proposed by Eglit et al. In particular, we wanted to determine if these indices would be associated with a specificity of at least.90, an Area Under the Curve of at least.70 and a positive likelihood ratio of at least 2. Method: We used logistic regression to investigate how well these indices could distinguish persons with traumatic brain injury (n = 169) who were evaluated within 1-12 months after injury. All participants had been classified on the basis of at least three independent performance validity tests as valid performance (n = 145) or invalid performance (n = 24). Results: None of the three indices that Eglit et al. had proposed as embedded performance measures for the D–KEFS Color Word Interference Test achieved the a priori defined minimally acceptable level of specificity. One of them did meet the criteria for Area Under the Curve as well as positive likelihood ratio. Conclusion: The current results do not support the application of the Eglit et al. embedded performance validity measures for the D–KEFS Color Word Interference Test in the clinical evaluation of patients with traumatic brain injury. [ABSTRACT FROM AUTHOR]

While the Neuropsychological Assessment Battery, Screening Module (S-NAB) is a commonly used cognitive screening measure, no composite embedded performance validity test (PVT) formula has yet been described within it. This study sought to empirically derive PVT formulas within the S-NAB using an analog simulation paradigm. Seventy-two university students (M age = 18.92) were randomly assigned to either an Asymptomatic (AS) or simulated mild traumatic brain injury (S-mTBI) group and were administered a neuropsychological test battery that included the S-NAB and standalone and embedded PVTs. The AS group was instructed to perform optimally, and the S-mTBI group received symptom and test coaching to help simulate mTBI-related impairment. Both groups received warnings regarding the presence of PVTs throughout the test battery. Groups showed significant differences (all ps <.001) on all S-NAB domain scores and PVTs. In the S-NAB, the Attention (S-ATT) and Executive Function (S-EXE) domains showed the largest effect sizes (Cohen's ds = 2.02 and 1.79, respectively). Seven raw scores from S-ATT and S-EXE subtests were entered as predictor variables in a direct logistic regression (LR). The model accurately classified 90.3% of cases. Two PVT formulas were described: (1) an exponentiated equation from LR results and (2) an arithmetic formula using four individually meaningful variables. Both formulas demonstrated outstanding discriminability between groups (AUCs =.96–.97) and yielded good classification statistics compared to other PVTs. This study is the first to describe composite, embedded PVT formulas within the S-NAB. Implications, limitations, and appropriate future directions of inquiry are discussed. [ABSTRACT FROM AUTHOR]

Objective: Performance validity assessment is a crucial component of any neuropsychological evaluation, particularly in settings where potential exaggeration of complaints and deficits is heightened. Standalone performance validity measures can be time-consuming, so many investigations have explored embedded indices within existing measures. The Rey Auditory Verbal Learning Test (RAVLT) and the Rey–Osterrieth Complex Figure Test (ROCF) each have a number of available embedded performance validity tests (PVTs). This investigation sought to evaluate several of these indices and to identify the most effective within a VA mild traumatic brain injury (mTBI)/Polytrauma sample. Method: A sample of 100 U.S. military veterans underwent clinical neuropsychological evaluation. There were 37 individuals whose test results were considered invalid based on failure of 2 or more independent PVTs, 47 whose results were valid, and 16 whose results were equivocal (failure on one PVT). The classification accuracies of published PVTs from the RAVLT and ROCF were evaluated. Results: Several indices had sensitivity values above 50% and strong positive predictive power with specificity held over 90%. Conclusions: The results demonstrated that there are multiple effective RAVLT & ROCF PVTs available for use in mTBI evaluations with veterans. [ABSTRACT FROM AUTHOR]

This study examined the relationship among performance validity test (PVT) failure, number of PVTs administered, and participant characteristics including demographic, diagnostic, functional, and contextual factors in a clinical sample (N= 158) of outpatient physiatry referrals. The number of PVTs failed and the number administered showed a small non-significant correlation (rs= .13,p= .10). Participant characteristics showed associations with PVT failure consistent with prior research. A negative binomial regression model was fitted using number of PVTs failed as outcome and age, education, number of PVTs administered, clinical versus medico-legal context, and functional status as predictors. Although education and functional status were significant predictors of number of PVTs failed, the number of PVTs administered was not. A second analytic approach focused on observed false positive rates in a neurologic no-incentive (NNI) sample subset (n= 87). In contrast to a recent proposal based on statistical simulation, observed false positive rates were lower than predicted rates in NNI participants administered six, seven, or eight PVTs using a two-PVT failure cutoff. These results are interpreted as mitigating concerns that increased PVT failure is necessarily the outcome of increased PVT administration. [ABSTRACT FROM AUTHOR]

The Rey Word Recognition Test, a brief and simple to administer free-standing neurocognitive performance validity test, was examined in a large known-groups sample (122 credible patients and 134 non-credible patients). Total correctly recognized was the most sensitive score, identifying 54% of non-credible participants using a cut-off of ≤6, while maintaining specificity of approximately 90%. However, specifically rates were somewhat lower in credible individuals with <12 years of education or borderline intelligence, or who were bilingual (spoke English as a second language, or learned English concurrently with another language), indicating that cut-offs may require minor adjustment in these groups. Sensitivity rates were much higher in non-credible female versus male mild traumatic brain injury patients (mTBI; 68% versus 48% for total correct), suggesting that the Rey Word Recognition Test is particularly effective in identifying performance invalidity in female mTBI compensation seekers. [ABSTRACT FROM PUBLISHER]

The b Test (Boone, Lu, & Herzberg, 2002a) is a measure of cognitive performance validity originally validated on 91 non-credible participants and 7 credible clinical comparison groups (totaln = 161). The purpose of the current study was to provide cross-validation data for the b Test on a known groups sample of non-credible participants (n = 212) and credible heterogeneous neuropsychological clinic patients (n = 103). The new data showed that while the original E-score cut-off of ≥155 achieved excellent specificity (99%), it was associated with relatively poor sensitivity (41%). However, the cut-off could be substantially lowered to ≥82, while still maintaining adequate specificity (≥90%) and raising sensitivity to 68%. Examination of non-credible subgroups revealed that b Test sensitivity in feigned mild traumatic brain injury (mTBI) was 58%, whereas in non-credible patients claiming depression and psychosis, cut-off sensitivity was 76% and 67%, respectively. These data suggest that the b Test may have a particular role in detection of non-credible cognitive symptoms associated with feigned psychiatric symptoms, and that fabricated deficits in processing speed and vigilance/visual scanning, detected by the b Test, are more prominent in feigned psychiatric presentations than in feigned mTBI. Further, b Test failures in patients with somatoform disorders were common, indicating that the b Test may have a specific use in detection of non-consciously created cognitive dysfunction associated with somatoform conditions. [ABSTRACT FROM PUBLISHER]

Embedded symptom validity measures facilitate the detection of below-capacity performance in neuropsychological assessment. A number of such indicators have been proposed for the Controlled Oral Word Association Test (COWAT), a widely used test of word generation. However, several of these embedded indicators have not been cross-validated and it is currently unclear which represent the optimal combination of predictors. This study used Bayesian Model Averaging (BMA) to determine the set of predictors that best differentiate between patients presenting with (n = 46) and without (n = 55) malingered neurocognitive dysfunction (MND). Mild traumatic brain injury was the most common diagnosis in the MND group (96%). BMA selected the COWAT total score and a measure of change in output over time. A logistic regression model combining these variables yielded good discriminability, with an AUC of. 774, (95% confidence interval = .679 to. 869), 78% of cases were classified correctly, with 67% sensitivity and 88% specificity. Two alternative models performed similarly, but the variables involved required slightly longer administration and/or calculation time, making them somewhat less desirable. These results support the use of a weighted combination of embedded symptom validity measures in the COWAT. [ABSTRACT FROM AUTHOR]

This investigation examined the test-retest reliability and the factorial validity of the Children's Color Trails Test 1 & 2 (CCTT) using two distinct and independent studies and their respective research samples. The reliability of the CCTT was evaluated in a study with 6-12-year-old children (n = 54) strictly selected and diagnosed with attention-deficit/hyperactivity disorder from an interventional protocol using test-retest coefficients at 8- and 16-week time intervals. Factorial validity was investigated using groups of children with traumatic brain injury (TBI) (n = 137), children with other types of trauma than brain or head injury (Other Injury) (n = 132), and healthy controls (n = 114) from a protocol assessing the neuropsychological sequelae of traumatic brain injury. The results revealed completion time test-retest reliability in the moderate range, which may be considered modest (rtt =.46-.68) in this sample of children with ADHD. Interference reliability coefficients were greater and in the moderate-high range (rtt =.75-.78). Factorial analytic results revealed a three-factor structure solution for all three groups (TBI, Other Injury, and controls). As a result of CCTT's factorial loadings, Factor 1 was labeled speed of perceptual tracking and susceptibility to interference, Factor 2 was labeled inattention and impulsivity, and Factor 3 was labeled simple inattention. Relative limitations and strengths associated with this investigation including practice effects associated with repeated CCTT administrations also were addressed within the context of the extant findings and existing trail-making test literature. [ABSTRACT FROM AUTHOR]

Many studies have reported on the pattern of neuropsychological test performance across varied seizure diagnosis populations. Far fewer studies have evaluated the accuracy of the clinical neuropsychologist in formulating an impression of the seizure diagnosis based on results of neuropsychological assessment, or compared the accuracy of clinical neuropsychological judgment to results of statistical prediction. Accuracy of clinical neuropsychological versus statistical prediction was investigated in four seizure classification scenarios. While both methods outperformed chance, accuracy of clinical neuropsychological classification was either equivalent or superior to statistical prediction. Results support the utility and validity of clinical neuropsychological judgment in epilepsy treatment settings. [ABSTRACT FROM AUTHOR]

The present study used a known-groups design to determine the classification accuracy of 10 MMPI-2 validity scales and indicators in the detection of cognitive malingering in traumatic brain injury. Participants were 259 traumatic brain injury and 133 general clinical patients seen for neuropsychological evaluation. The TBI patients were subdivided into groups based on a comprehensive examination of effort following Slick, Sherman, and Iverson's (1999) criteria. More extreme scores demonstrated excellent specificity; often impressive sensitivity was seen even while maintaining a low false positive error rate. Specificity was good even in stroke, memory disorder, and psychiatric patients without incentive. The results of this study are presented in frequency tables that can be easily referenced in clinical practice. [ABSTRACT FROM AUTHOR]

The Wisconsin Card Sorting Test-64(WCST-64)is a recently normed modification of the Wisconsin Card Sorting Test(WCST)that utilizes only one deck of cards. The present study investigated the validity of the WCST-64 in a sample of fifty-six 10- to 16-year-old children with traumatic brain injury(TBI). Standard scores for perseverative responses from the WCST-64 and from the full-length WCST shared 83%of common variance. Less than 10%of this sample had a discrepancy between the respective indexes that was greater than one standard deviation. Correlations with external criteria such as length of coma and Full Scale IQ were not significantly different between the two versions of the instrument. The findings suggest that the WCST-64 may be used interchangeably with the original WCST in older children with TBI. [ABSTRACT FROM AUTHOR]