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A number of performance validity tests (PVTs) are used to assess memory complaints associated with traumatic brain injury (TBI); however, few studies examine the concordance and predictive accuracy of multiple PVTs, specifically in the context of combined models in known-group designs. The present study compared five widely used PVTs: the Test of Memory Malingering (TOMM), Medical Symptom Validity Test (MSVT), Reliable Digit Span (RDS), Word Choice Test (WCT), and California Verbal Learning Test - Forced Choice (CVLT-FC). Participants were 51 adults with bona fide moderate to severe TBI and 58 demographically comparable healthy adults coached to simulate memory impairment. Classification accuracy of individual PVTs was evaluated using logistic regression and receiver operating characteristic (ROC) curves, examining both the dichotomous cutting scores as recommended by the test publishers and continuous scores for the measures. Results demonstrated nearly equivalent discrimination ability of the TOMM, MSVT, and CVLT-FC as individual predictors, all of which markedly outperformed the WCT and RDS. Models of combined PVTs were examined using Bayesian information criterion statistics, with results demonstrating that diagnostic accuracy showed only small to modest growth when the number of tests was increased beyond two. Considering the clinical and pragmatic issues in deriving a parsimonious assessment battery, these findings suggest that using the TOMM and CVLT in conjunction or the MSVT and CVLT in conjunction maximized predictive accuracy as compared to a single index or an assortment of these widely used measures.

Reliable Digit Span (RDS) is a measure of effort derived from the Digit Span subtest of the Wechsler intelligence scales. Some authors have suggested that the age-corrected scaled score provides a more accurate measure of effort than RDS. This study examined the relative diagnostic accuracy of the traditional RDS, an extended RDS including the new Sequencing task from the Wechsler Adult Intelligence Scale-IV, and the age-corrected scaled score, relative to performance validity as determined by the Test of Memory Malingering. Data were collected from 138 Veterans seen in a traumatic brain injury clinic. The traditional RDS (≤ 7), revised RDS (≤ 11), and Digit Span age-corrected scaled score ( ≤ 6) had respective sensitivities of 39%, 39%, and 33%, and respective specificities of 82%, 89%, and 91%. Of these indices, revised RDS and the Digit Span age-corrected scaled score provide the most accurate measure of performance validity among the three measures.

This study examined embedded performance validity indicators (PVI) based on the number of impaired scores in an evaluation and the overall test battery mean (OTBM). Adult participants (N = 175) reporting traumatic brain injury were grouped using eight PVI. Participants who passed all PVI (n = 67) demonstrated fewer impaired scores and higher OTBM than those who failed two or more PVI (n = 66). Impairment was defined at three levels: T scores < 40, 35, and 30. With specificity ≥.90, sensitivity ranged from .51 to .71 for number of impaired scores and .74 for OTBM.

This study examined the relationship of performance validity and neuropsychological outcomes in a sample of individuals referred for independent neuropsychological examination in the context of reported traumatic brain injury (82% mild). Archival data were examined on 175 participants aged 20 to 65 who were administered at least two performance validity measures. Participants who passed all effort measures (Pass; n = 61) outperformed those who failed two or more (Fail; n = 70) on the majority of tests in the neuropsychological battery. The Fail group showed a higher percentage of impaired test scores than the Pass group with impairment defined at three levels (T scores < 40, 35, and 30). At the most conservative impairment cutoff (T < 30), 16% of the Pass group demonstrated impaired scores on more than three measures, while 79% of the Fail group showed impaired scores on more than three measures. The number of effort measures failed correlated highly with the overall test battery mean (r = -.73). On cognitive domain summary scores, effect sizes based on levels of effort (d = 1.12 to 1.86) were higher than those based on injury severity (d = 0.03 to 0.36).

This study derived an embedded performance validity indicator for the Rey Auditory Verbal Learning Test (AVLT) using an archival dataset. Participants aged 20 to 65 (N = 167) who reported traumatic brain injury and completed at least two performance validity tests were included. The group who passed all performance validity measures (n = 68) demonstrated higher scores on all AVLT trials than the group who failed two or more validity indicators (n = 62). Bayesian model averaging was used to identify the optimal combination of AVLT variables for group discrimination; Total Learning and Recognition raw scores were selected. Logistic regression using these variables showed excellent discrimination with an area under the curve of. 85. The resulting AVLT performance validity index demonstrated sensitivity of. 55 with specificity of. 91. Further study of this index is warranted and cross-validation is recommended prior to clinical use.

A sample of 314 consecutive clinical and forensic referrals with mild traumatic brain injury was evaluated using the Meyers Neuropsychological Battery (MNB). A comparison was made of the test performance and performance on the embedded Symptom Validity Tests (SVTs) with a control for multicolinearity utilized. Using the nine embedded SVTs in the MNB, the incidence of poor effort fell at 26% of the total sample. Involvement in litigation was related to more failures on the individual SVTs. The correlation between failed effort measures and the Overall Test Battery Mean (OTBM) was consistently negative, regardless of litigation status, in that more failures were associated with lower OTBM scores. The correlation between the number of SVTs failed and the OTBM was -.77. Our results are similar to those presented by Green, Rohling, Lees-Haley, and Allen (2001); who reported a .73 correlation with the failure on the Word Memory Test and performance on the OTBM. The results of the current study also indicate that 50% of the variance in neuropsychological testing can be accounted by failures on internal SVTs.

The Traumatic Brain Injury Screening Instrument (TBISI) was implemented in Veterans Affairs medical facilities in an attempt to identify Operation Enduring Freedom and Operation Iraqi Freedom (OEF/OIF) veterans with possible mild TBI. Despite its widespread implementation, the reliability and validity of the screening tool has not yet been established. The current study reports preliminary findings on the test-retest reliability of the TBISI in 44 OEF/OIF veterans referred for neuropsychological evaluation following a positive TBI screen. Results suggest overall poor test-retest reliability of the TBI screening tool with regard to type of event, injuries sustained, and resulting sequelae. These findings underscore the importance of further investigation of its psychometric properties to promote accurate identification and referral of veterans with possible TBI.

The Postconcussive Symptom Questionnaire (PCSQ) was developed to assess the symptoms associated with the controversial diagnosis of postconcussion syndrome. We examined item endorsement on the PCSQ in two groups. The first group was made up of individuals diagnosed with moderate to severe traumatic brain injury. The second group was made up of individuals meeting criteria for mild traumatic brain injury who exhibited no evidence of neurological injury. In addition, they demonstrated poor effort during neuropsychological examination. Significant differences in item endorsement were found the majority of individual items as well as on the PCSQ indices. The poor effort mild traumatic brain injury group consistently reported more symptoms with greater severity. The results raise further questions about the validity of postconcussion symptoms.

Objective: To examine the nature of agitation in patients with brain injury and quantify the relation between agitation and patient progress in rehabilitation., Design: Cross-sectional, correlational., Setting: Urban, inpatient rehabilitation facility in the midwestern United States., Participants: Sixty-nine patients with acquired brain injury admitted to an acute rehabilitation hospital., Main Outcome Measures: Therapy Engagement using the Rehabilitation Therapy Engagement Scale; Functional Status using the Functional Independence Measure., Results: Agitated behavior was inversely associated with engagement in rehabilitation therapy even after controlling for injury severity. Engagement in therapy mediated the relation between agitated behavior and progress in rehabilitation as assessed using a Functional Independence Measure efficiency ratio., Conclusions: Progress in acute brain injury rehabilitation appears to be meaningfully influenced by the complex interplay among injury severity, agitation, and engagement. The findings are consistent with a theoretical model, suggesting that agitated patients make less progress in rehabilitation not only because of greater injury severity but also because agitation disrupts engagement in rehabilitation therapies. Multiple clinical purposes may be better served by measuring behavioral excess on a continuum than in a dichotomous fashion.

The current study evaluated the utility of the Digit Span subtest in discriminating patients with mild head trauma from individuals referred for independent neuropsychological evaluation with objective evidence of poor effort. Various indices from the Digit Span subtest were evaluated to determine the best discriminator of brain injury from poor motivation patient groups: Digit Span Forward, Digit Span Backwards, Reliable Digit Span, Digit Span Age-Corrected Scaled Score, and the difference score between the Vocabulary and Digit Span scaled scores. The Digit Span scaled score was found to be the best discriminating index. A cutoff score of less than or equal to 7 accurately classified 75% of persons in the incomplete effort group and 69% of persons in the TBI group. Application of this cutoff score to a non-litigating mild brain injury group yielded a 77% correct classification rate. However, Digit Span scaled score accounted for a modest amount of variation and it is not recommended as a stand-alone validity measure.

WAIS-III profile interpretation typically involves the analysis of disparities between summary and subtest scores. Determination of clinically meaningful differences has been guided by published rates of discrepancies based upon the normative sample. However, noting that a particular profile discrepancy is uncommon among normals only represents one step in the interpretive process. Rates of such pairwise differences have yet to be published for clinical samples. In order to begin filling this void in the literature, we present frequencies of composite and subtest differences from a postacute traumatic brain injury sample. The practical utility of these tables, in conjunction with the normative tables, is demonstrated.

Objective:The present study evaluated strategies used by healthy adults coached to simulate traumatic brain injury (TBI) during neuropsychological evaluation.Method:Healthy adults (n = 58) were coached to simulate TBI while completing a test battery consisting of multiple performance validity tests (PVTs), neuropsychological tests, a self-report scale of functional independence, and a debriefing survey about strategies used to feign TBI.Results:“Successful” simulators (n = 16) were classified as participants who failed 0 or 1 PVT and also scored as impaired on one or more neuropsychological index. “Unsuccessful” simulators (n = 42) failed ≥2 PVTs or passed PVTs but did not score impaired on any neuropsychological index. Compared to unsuccessful simulators, successful simulators had significantly more years of education, higher estimated IQ, and were more likely to use information provided about TBI to employ a systematic pattern of performance that targeted specific tests rather than performing poorly across the entire test battery.Conclusion:Results contribute to a limited body of research investigating strategies utilized by individuals instructed to feign neurocognitive impairment. Findings signal the importance of developing additional embedded PVTs within standard cognitive tests to assess performance validity throughout a neuropsychological assessment. Future research should consider specifically targeting embedded measures in visual tests sensitive to slowed responding (e.g. response time). [ABSTRACT FROM PUBLISHER]

Objective: This study explored the utility of combining data from measures of performance validity and symptom validity among Veterans undergoing neuropsychological evaluation for mild traumatic brain injury (mTBI). Background: Persistent cognitive impairments following mTBI are often reported by returning combat veterans. However, objectively-measured cognitive deficits are not common among individuals with mTBI, raising the question of whether negative impression management influences self-ratings. Methods: Self-report ratings were obtained for memory, concentration, decision-making, and processing speed/organization using a 5-point scale ranging from 'none' to 'very severe'. Veterans also completed brief neuropsychological testing which included measures of performance validity. Results: Study 1 examined data from 122 participants and demonstrated that veterans reporting a 'very severe' cognitive deficit were over three times as likely to demonstrate poor effort on a validity test than those without a very severe rating. Study 2 replicated these findings in an independent sample of 127 veterans and also demonstrated that both severity of self-report ratings and performance on an embedded measure of effort were predictive of poor effort on a stand-alone performance validity test. Conclusion: Veterans with suspected mTBI who report 'very severe' cognitive impairment have a greater likelihood of putting forth sub-optimal effort on objective testing. [ABSTRACT FROM AUTHOR]

Introduction: The Mild Brain Injury Atypical Symptoms (mBIAS) scale was developed as a symptom validity test (SVT) for use with patients following mild traumatic brain injury. This study was the first to examine the clinical utility of the mBIAS in a mixed clinical sample presenting to a Department of Veterans Affairs (VA) neuropsychology clinic.Method: Participants were 117 patients with mixed etiologies (85.5% male; age:M= 39.2 years,SD= 11.6) from a VA neuropsychology clinic. Participants were divided into pass/fail groups using two different SVT criteria, based on select validity scales from the Minnesota Multiphasic Personality Inventory–2 (MMPI–2): first, Infrequency Scale (F) scores: (a) MMPI–F–Fail (n= 21) and (b) MMPI–F–Pass (n= 96); and, second, Symptom Validity Scale (FBS) scores: (a) MMPI–FBS–Fail (n= 36) and (b) MMPI–FBS–Pass (n= 81).Results: The mBIAS demonstrated good internal consistency, and each item contributed meaningfully to the total score. At a symptom exaggeration base rate of 35%, an mBIAS cutoff of ≥11 was optimal for screening symptom exaggeration when groups were classified using both F and FBS scales. This cutoff score resulted in very high specificity (.89 to .94); moderate–high positive predictive power (.71 to .75) and negative predictive power (.72 to .79); and low–moderate sensitivity (.31 to .57). At all base rates of probable somatic exaggeration, a cutoff of ≥16 resulted in perfect specificity and positive predictive power, but very low sensitivity.Conclusions: The mBIAS has potential for use in samples outside of mild traumatic brain injury. In settings where the symptom exaggeration base rate is 35%, a cutoff of ≥11 may be used as a “red flag” for further evaluation, but should not be relied on for clinical decision making. At all base rates of probable somatic exaggeration, psychologists with patients who score ≥16 can be confident that those patients were exaggerating. Importantly, however, this cutoff may fail to identify a large proportion of patients who are exaggerating. [ABSTRACT FROM PUBLISHER]

The purpose of this study was to determine how well scores from the Rey Complex Figure Test (RCFT) could serve as embedded measures of performance validity in a large, heterogeneous clinical sample at an urban-based Veterans’ Affairs hospital. Participants were divided into credible performance (n = 244) and noncredible performance (n = 87) groups based on common performance validity tests during their respective clinical evaluations. We evaluated how well preselected RCFT scores could discriminate between the 2 groups using cut scores from single indexes as well as multivariate logistic regression prediction models. Additionally, we evaluated how well memory error patterns (MEPs) could discriminate between the 2 groups. Optimal discrimination occurred when indexes from the Copy and Recognition trials were simultaneous predictors in logistic regression models, with 91% specificity and at least 53% sensitivity. Logistic regression yielded superior discrimination compared with individual indexes and compared with the use of MEPs. Specific scores on the RCFT, including the Copy and Recognition trials, can serve as adequate indexes of performance validity, when using both cut scores and logistic regression prediction models. We provide logistic regression equations that can be applied in similar clinical settings to assist in determining performance validity. [ABSTRACT FROM PUBLISHER]

This study investigated the ability of the Wechsler Memory Scale-4th Edition (WMS-IV) and the Advanced Clinical Solutions (ACS) package including the new Word Choice test (WCT) to distinguish poor performance due to intentional response bias among simulators of traumatic brain injury (TBI) from poor performance due to actual TBI. Participants were 45 survivors of moderate to severe TBI and 39 healthy adult coached to simulate TBI. Logistic regression indicated that a five-variable model containing all the ACS variables and a single-variable model using only the WCT were statistically reliable. Comparing predictive accuracy of each model found that adding the WCT to the ACS increased predictive accuracy. Diagnostic efficiency for the full ACS model was considered 'excellent' according to interpretive guidelines. [ABSTRACT FROM AUTHOR]

Publication of the third editions of the Wechsler intelligence and memorybatteries in 1997 created a need for research identifying Wechsler Adult IntelligenceScale-Third Edition/Wechsler Memory Scale-Third Edition (WAIS-III/WMS-III)profile patterns associated with neuropathology. The WAIS-III/WMS-III TechnicalManual offers data on various diagnostic groups, including traumatic braininjury (TBI). Hawkins (1998) employed Technical Manual data to propose certaindiagnostic guidelines. In order to validate the conclusions put forth by Hawkinsas they apply to brain injury, we examined WAIS-III and WMS-III profiles inan independent sample of 46 TBI cases. As expected, the WAIS-III ProcessingSpeed Index (PSI) was more sensitive to brain injury than other WAIS-III composites;and specific WAIS-III scores were stronger than certain WMS-III scores. Onthe other hand, the predicted relationship for WMS-III auditory and visualindexes was not found. The lack of specificity for TBI of the proposed indexcomparisons confirms the need to validate such hypotheses in independent samples. [ABSTRACT FROM AUTHOR]

Arithmetic algorithms for predicting premorbid Full Scale IQ were evaluated in a sample of 125 brain injured adults who had been evaluated within two months of their injury, and then again one year later. FSIQ at post-test was used as the criterion variable. The prediction equation, based on demographic information only (Barona, Chastain, & Reynolds, 1984), proved to be a modest predictor of premorbid FSIQ. The BEST-3 (Vanderploeg & Schinka, 1995), a prediction equation that incorporates demographic information and performance data, was sensitive to the severity of the brain injury. Subsequent analyses found the BEST-3 to be a better predictor of recovery of function than it was an estimate of premorbid functioning. This study demonstrates the need for flexibility in the interpretation of results, as what was thought to be a prediction equation for premorbid functioning was better viewed as an estimate of recovery. [ABSTRACT FROM AUTHOR]

Objective: To examine the properties of the Rehabilitation Therapy Engagement Scale (RTES), a new scale developed to assess patient engagement in physical and occupational therapies in the acute rehabilitation setting quantitatively. Design: Psychometric analysis to test the reliability and validity of the RTES in a Midwestern acute rehabilitation facility. Participants: 75 individuals with acquired brain injury admitted to an acute rehabilitation program in a Midwestern urban setting. Main Outcome Measures: Physical therapists (PTs) and occupational therapists (OTs) completed a rating scale designed to measure each patient's level of engagement, or involvement, in therapy. Functional status at admission and discharge was measured with the Motor and Cognition scales of the Functional Independence Measure (FIM; J. M. Linacre, A. W. Heinemann, B. D. Wright, C. V. Granger, B. B. Hamilton, 1994). Results: The RTES showed high internal consistency in both physical therapy and occupational therapy settings, as well as significant correlation across those settings (r = .56, p < .001). Conclusions: The RTES appears to be a reliable and relatively unidimensional measure to identify and describe issues affecting patient engagement in rehabilitation therapies. Additional research is suggested to better understand and define the construct of engagement and to provide additional evidence of convergent and discriminant validity in the RTES. [ABSTRACT FROM AUTHOR]