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Objectives: This study investigated the Wechsler Adult Intelligence Scale-Fourth Edition Letter-Number Sequencing (LNS) subtest as an embedded performance validity indicator among adults undergoing an attention-deficit/hyperactivity disorder (ADHD) evaluation, and its potential incremental value over Reliable Digit Span (RDS). Method: This cross-sectional study comprised 543 adults who underwent neuropsychological evaluation for ADHD. Patients were divided into valid ( n  = 480) and invalid ( n  = 63) groups based on multiple criterion performance validity tests. Results: LNS total raw scores, age-corrected scaled scores, and age- and education-corrected T-scores demonstrated excellent classification accuracy (area under the curve of .84, .83, and .82, respectively). The optimal cutoff for LNS raw score (≤16), age-corrected scaled score (≤7), and age- and education-corrected T-score (≤36) yielded .51 sensitivity and .94 specificity. Slightly lower sensitivity (.40) and higher specificity (.98) was associated with a more conservative T-score cutoff of ≤33. Multivariate models incorporating both LNS and RDS improved classification accuracy (area under the curve of .86), and LNS scores explained a significant but modest proportion of variance in validity status above and beyond RDS. Chaining LNS T-score of ≤33 with RDS cutoff of ≤7 increased sensitivity to .69 while maintaining ≥.90 specificity. Conclusions: Findings provide preliminary evidence for the criterion and construct validity of LNS as an embedded validity indicator in ADHD evaluations. Practitioners are encouraged to use LNS T-score cutoff of ≤33 or ≤36 to assess the validity of obtained test data. Employing either of these LNS cutoffs with RDS may enhance the detection of invalid performance.

Objective: Differential diagnosis of attention deficit/hyperactivity disorder (ADHD) is one of the most common referral questions for neuropsychological evaluation but is complicated by the presence of external incentives. Validity assessment is therefore critical in such evaluations, employing symptom validity tests (SVTs) and performance validity tests (PVTs) to assess the validity of reported symptoms and cognitive test performance, respectively. This study aimed to establish the base rate of symptom and performance invalidity in adults referred for ADHD, compare concordance between performance and symptom validity, and assess the impact of each type of validity on cognitive test performance. Method: This consecutive case series included data from 392 demographically-diverse adults who underwent outpatient neuropsychological evaluation for ADHD. All patients were administered the Clinical Assessment of Attention Deficit-Adult (CAT-A) and a uniform cognitive test battery, including seven PVTs. Results: Invalid symptom reporting and PVT performance were found in 22% and 16% of the sample, respectively. Sixty-eight percent had concordantly valid SVTs/PVTs and 6% had invalid SVTs/PVTs, whereas the remaining 26% had either invalid SVTs or PVTs (but not both). Invalid PVT performance resulted in a significant decrease across all cognitive test scores, with generally large effects (η p 2 =.01-.18). Invalid symptom reporting had minimal effects on cognitive test performance (η p 2 = ≤.04). Conclusions: PVTs and SVTs are dissociable and therefore should not be used interchangeably in the context of adult ADHD evaluations. Rather, symptom and performance validity should continue to be assessed independently as they provide largely non-redundant information.

Objective: This study examined Dot Counting Test (DCT) performance among patient populations with no/minimal impairment and mild impairment in an attempt to cross-validate a more parsimonious interpretative strategy and to derive optimal E-Score cutoffs., Method: Participants included clinically-referred patients from VA ( n  = 101) and academic medical center (AMC, n  = 183) settings. Patients were separated by validity status (valid/invalid), and subsequently two comparison groups were formed from each sample's valid group. Namely, Group 1 included patients with no to minimal cognitive impairment, and Group 2 included those with mild neurocognitive disorder. Analysis of variance tested for differences between rounded and unrounded DCT E-Scores across both comparison groups and the invalid group. Receiver operating characteristic curve analyses identified optimal validity cut-scores for each sample and stratified by comparison groups., Results: In the VA sample, cut scores of ≥13 (rounded) and ≥12.58 (unrounded) differentiated Group 1 from the invalid performers (87% sensitivity/88% specificity), and cut scores of ≥17 (rounded; 58% sensitivity/90% specificity) and ≥16.49 (unrounded; 61% sensitivity/90% specificity) differentiated Group 2 from the invalid group. Similarly, in the AMC group, a cut score of ≥13 (rounded and unrounded; 75% sensitivity/90% specificity) differentiated Group 1 from the invalid group, whereas cut scores of ≥18 (rounded; 43% sensitivity/94% specificity) and ≥16.94 (unrounded; 46% sensitivity/90% specificity) differentiated Group 2 from the invalid performers., Conclusions: Different cut scores were indicated based on degree of cognitive impairment, and provide proof-of-concept for a more parsimonious interpretative paradigm than using individual cut scores derived for specific diagnostic groups.

Objective The Test of Memory Malingering (TOMM) Trial 1 (T1) and errors on the first 10 items of T1 (T1-e10) were developed as briefer versions of the TOMM to minimize evaluation time and burden, although the effect of genuine memory impairment on these indices is not well established. This study examined whether increasing material-specific verbal and visual memory impairment affected T1 and T1-e10 performance and accuracy for detecting invalidity. Method: Data from 155 neuropsychiatric patients administered the TOMM, Rey Auditory Verbal Learning Test (RAVLT), and Brief Visuospatial Memory Test-Revised (BVMT-R) during outpatient evaluation were examined. Valid ( N  = 125) and invalid ( N  = 30) groups were established by four independent criterion performance validity tests. Verbal/visual memory impairment was classified as ≥37 T (normal memory); 30 T-36T (mild impairment); and ≤29 T (severe impairment). Results: Overall, T1 had outstanding accuracy, with 77% sensitivity/90% specificity. T1-e10 was less accurate but had excellent discriminability, with 60% sensitivity/87% specificity. T1 maintained excellent accuracy regardless of memory impairment severity, with 77% sensitivity/≥88% specificity and a relatively invariant cut-score even among those with severe verbal/visual memory impairment. T1-e10 had excellent classification accuracy among those with normal memory and mild impairment, but accuracy and sensitivity dropped with severe impairment and the optimal cut-score had to be increased to maintain adequate specificity. Conclusion: TOMM T1 is an effective performance validity test with strong psychometric properties regardless of material-specificity and severity of memory impairment. By contrast, T1-e10 functions relatively well in the context of mild memory impairment but has reduced discriminability with severe memory impairment.

Objective: This cross-sectional study examined the effect of number of Performance Validity Test (PVT) failures on neuropsychological test performance among a demographically diverse Veteran (VA) sample ( n  = 76) and academic medical sample (AMC; n  = 128). A secondary goal was to investigate the psychometric implications of including versus excluding those with one PVT failure when cross-validating a series of embedded PVTs. Method: All patients completed the same six criterion PVTs, with the AMC sample completing three additional embedded PVTs. Neurocognitive test performance differences were examined based on number of PVT failures (0, 1, 2+) for both samples, and effect of number of criterion failures on embedded PVT performance was analyzed among the AMC sample. Results: Both groups with 0 or 1 PVT failures performed better than those with ≥2 PVT failures across most cognitive tests. There were nonsignificant differences between those with 0 or 1 PVT failures except for one test in the AMC sample. Receiver operator characteristic curve analyses found no differences in optimal cut score based on number of PVT failures when retaining/excluding one PVT failure. Conclusion: Findings support the use of ≥2 PVT failures as indicative of performance invalidity. These findings strongly support including those with one PVT failure with those with zero PVT failures in diagnostic accuracy studies, given that their inclusion reflects actual clinical practice, does not reduce sample sizes, and does not artificially deflate neurocognitive test results or inflate PVT classification accuracy statistics.

Objective: Primary angiitis of the central nervous system (PACNS) is a rare and devastating form of vasculitis that destroys the vessels of the brain and spinal cord, resulting in progressive and debilitating neurologic symptoms. The objective of the present study was to detail the diagnostic process of a case of a patient with PACNS who suffered from six intracerebral hemorrhages (ICHs)., Method: The patient was an African American woman with a history of recurrent ICHs of unclear etiology who received serial neuropsychological evaluations over the course of a 5-year period. Two comprehensive neuropsychological evaluations are included, as well as an overview of her clinical course, including differential diagnostic considerations and treatment planning., Results: Neuropsychological assessment revealed marked deficits in visuospatial abilities and processing speed associated with her underlying neuropathology. Integrated review of her medical records indicated a probable diagnosis of PACNS as the likely etiology of her recurrent ICHs., Conclusions: This study demonstrates the importance of differential diagnosis of low base-rate conditions, functional neuroanatomy and neurobehavioral phenomenology, serial assessment, and cognitive reserve in clinical neuropsychological practice.

Objective: This study cross-validated the word choice test (WCT) in a diverse neuropsychiatric sample and examined the effect of increasing verbal memory impairment severity on WCT performance., Method: Data from 147 clinically referred patients (113 valid/34 invalid) who completed the WCT, Rey Auditory Verbal Learning Test (RAVLT), and four independent criterion PVTs were analyzed. RAVLT memory impairment bands used were: ≥37T (normal memory); 30T-36T (below average scores/mild impairment); and ≤29T (extremely low scores/severe impairment)., Results: WCT and RAVLT were moderately correlated. The invalid group had significantly worse performance on the WCT and RAVLT. For the overall sample, the WCT yielded an area under the curve (AUC) = .79, with 62% sensitivity/93% specificity at a cut-score of ≤41. When the sample was subdivided by memory impairment severity, the severe impairment group had significantly lower WCT scores than the normal group. Moreover, the WCT retained moderate classification accuracy among the normal memory (AUC = .85) and mild memory impairment (AUC = .76) groups, with sensitivities of 65% and 62% (≥91% specificity) at their respective optimal cut-scores of ≤44 and ≤42. In contrast, the WCT had low classification accuracy among those with severe memory impairment (AUC = .66), with only 15% sensitivity/95% specificity at the optimal cut-score of ≤30., Conclusion: The WCT is generally useful for detecting invalid neuropsychological test performance, although, its classification accuracy was diminished among patients with severe memory impairment. Therefore, while the WCT remains a viable option for performance validity assessment, neuropsychologists should carefully consider its use when this level of severe memory impairment is known or suspected.

Objective: Electrical injury (EI) is a distinct subtype of traumatic injury that often results in a unique constellation of cognitive sequelae and unusual sensory experiences due to peripheral nervous system injury that are uncommon in general medical/neurological populations and have been unexplored with the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF). Method: This study examined performance patterns on MMPI-2-RF validity and substantive scales among 62 EI patients who underwent neuropsychological evaluation, of which 46 demonstrated valid symptom reporting and neurocognitive test performance via multiple independent validity indicators and were retained for analysis. Results: Valid EI patients scored significantly higher than the MMPI-2-RF normative sample on several validity scales with the largest effect sizes on F-r (Infrequent Responses), Fs (Infrequent Somatic Responses), FBS-r (Symptom Validity), and RBS (Response Bias), and ≥33% obtaining elevated scores on these scales per standard interpretive criteria. Review of item content on these scales revealed several reflect disturbances in sensation, physical functioning, and/or cognition that are not infrequent in this population. Further, MMPI-2-RF clinical profiles did not reveal generalized distress or noncredible over-reporting. Rather, similar to the MMPI-2, valid EI patients had a specific pattern related to physical/sensory symptoms and reduced positive emotions with elevations on restructured clinical (RC) scale 1 (somatic complaints), somatic/cognitive specific problem scales, and low positive emotions (RC2). Conclusions: Elevations on some MMPI-2-RF validity scale may capture some degree of actual EI sequela that neuropsychologists need to consider to prevent erroneously concluding that a credible EI patient is over-reporting when s/he is reporting bona fide, EI-related symptoms.