Robert J. Spencer

Self-reported cognitive symptoms following mild traumatic brain injury are poorly associated with neuropsychological performance in OIF/OEF veterans

Mild traumatic brain injury (mTBI) is not uncommon among Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) veterans, and many individuals within this group report lingering cognitive difficulties following their injury. For Department of Veterans Affairs clinicians, an accurate assessment of cognitive symptoms is important in providing appropriate clinical care. Although self-assessment is commonly employed to screen for difficulties in cognitive functioning, little is known about the accuracy of self-report in this population. This study collected cognitive, psychiatric, and self-report data from 105 OIF/OEF veterans with mTBI to examine the relationship between self-reported cognitive functioning and objective neuropsychological test performance. Additionally, clinicians who frequently work with OIF/OEF veterans were asked to predict the magnitude of these associations. Self-reported cognitive functioning was not significantly correlated with objective cognitive abilities, suggesting that objective neuropsychological testing should be used when cognitive weakness is suspected. Perceived cognitive deficits were associated with depression, anxiety, and posttraumatic stress disorder, illustrating the additional importance of adequate assessment and treatment of psychiatric symptoms. Clinicians tended to overestimate the association between self-report and test performance.

The contributions of self-reported injury characteristics and psychiatric symptoms to cognitive functioning in OEF/OIF veterans with mild traumatic brain injury.

Mild traumatic brain injury (mTBI) affects a significant number of combat veterans returning from Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF). Although resolution of mTBI symptoms is expected over time, some individuals continue to report lingering cognitive difficulties. This study examined the contributions of self-reported mTBI injury characteristics (e.g., loss of consciousness, post-traumatic amnesia) and psychiatric symptoms to both subjective and objective cognitive functioning in a sample of 167 OEF/OIF veterans seen in a TBI clinic. Injury characteristics were not associated with performance on neuropsychological tests but were variably related to subjective ratings of cognitive functioning. Psychiatric symptoms were highly prevalent and fully mediated most of the relationships between injury characteristics and cognitive ratings. This indicates that mTBI characteristics such as longer time since injury and loss of consciousness or post-traumatic amnesia can lead to increased perceived cognitive deficits despite having no objective effects on cognitive performance. Psychiatric symptoms were associated with both cognitive ratings and neuropsychological performance, illustrating the important role that psychiatric treatment can potentially play in optimizing functioning. Finally, subjective cognitive ratings were not predictive of neuropsychological performance once psychiatric functioning was statistically controlled, suggesting that neuropsychological assessment provides valuable information that cannot be gleaned from self-report alone.

WAIS-IV Reliable Digit Span is no More Accurate Than Age Corrected Scaled Score as an Indicator of Invalid Performance in a Veteran Sample Undergoing Evaluation for mTBI

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.

Limited usefulness of the Rey Fifteen-Item Test in detection of invalid performance in veterans suspected of mild traumatic brain injury

Abstract Objective: This study explored using the FIT as a measure of performance validity among veterans undergoing neuropsychological evaluation for mild traumatic brain injury (mTBI). Background: The Rey Fifteen-Item Memory Test (FIT) is a performance validity measure criticized for poor sensitivity. Methods: Two hundred and fifty-seven veterans completed the FIT and Wechsler Adult Intelligence Scale, Fourth Edition, Digit Span (DS); 109 of whom completed the Test of Memory Malingering (TOMM). FIT cut-offs of <9, <8 and stricter cut-offs were examined using DS and/or TOMM as criterion performance validity measures. Results: Only four participants scored below the standard cut score of 9 on the FIT. Among the 13 veterans failing both criterion tests, only two scored below 9 on the FIT. Regardless of which FIT cut-off was used, the FIT had poor diagnostic accuracy. Conclusion: Despite its popularity, the FIT is not supported as an appropriate measure of performance validity in veterans undergoing evaluation for possible mTBI. Therefore, inferences regarding neuropsychological data reliability with adequate statistical certainty require use of other measures of performance validity with greater sensitivity.

Neuropsychological test validity in Veterans presenting with subjective complaints of ‘very severe’ cognitive symptoms following mild traumatic brain injury

Abstract 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.

Informational literature influences symptom expression following mild head injury: An analog study

Abstract Primary objective: Many Veterans involved in recent OEF/OIF conflicts return with reports of having experienced an mTBI. The Veteran’s Affairs (VA) and Department of Defense (DoD) have gone to great lengths to provide information to Veterans regarding possible effects of TBI. Although well intended, this information may possibly have an iatrogenic effect. Conversely, setting positive expectations for recovery from mTBI has been shown to result in decreased symptomatology. Research design: One-way ANOVA and Tukey post-hoc analyses were used to determine whether there were significant differences on reported severity and number of PCS symptoms (NSI) among the three experimental groups (recovery focused information; expectation for persistent symptoms; and no information given). Methods and procedures: Undergraduate students, who were told to imagine they had experienced a military-related TBI, reported varying levels of expected symptoms when given either positive or negative information about symptom expectation. Main outcomes and results: The results indicate that presenting recovery-oriented literature resulted in the lowest report of expected symptoms, whereas presenting no information resulted in the highest report of expected symptoms. Conclusions: Providing Veterans with information regarding a likely positive trajectory of recovery may result in less symptom persistence during rehabilitation.

Reliability and factor structure of the hospital anxiety and depression scale in a polytrauma clinic

The Hospital Anxiety and Depression Scale (HADS) is a brief self-report measure of anxiety and depression symptoms. This study examined the internal consistency and factor structure of the HADS among Veterans in a polytrauma/traumatic brain injury clinic. The sample consisted of 312 Veterans. A confirmatory factor analysis of the depression and anxiety subscales showed, not surprisingly, that the two factors were highly correlated (r = 0.7). Goodness of fit statistics for the two-factor model were acceptable (root mean square error of approximation = 0.06, comparative fit index = 0.94). The HADS demonstrated very good reliability overall (alpha = 0.89) and for the individual subscales (alpha = 0.84). This study supports the use of the HADS as a screen for depression and anxiety in the assessment of mild traumatic brain injury in a Veteran population.

Incidental Learning: A Brief, Valid Measure of Memory Based on the WAIS–IV Vocabulary and Similarities Subtests

Objective:We assessed the validity of a brief incidental learning measure based on the Similarities and Vocabulary subtests of the Wechsler Adult Intelligence Scale–Fourth Edition (WAIS–IV). Background:Most neuropsychological assessments for memory require intentional learning, but incidental learning occurs without explicit instruction. Incidental memory tests such as the WAIS–III Symbol Digit Coding subtest have existed for many years, but few memory studies have used a semantically processed incidental learning model. Methods:We conducted a retrospective analysis of 37 veterans with traumatic brain injury, referred for outpatient neuropsychological testing at a Veterans Affairs hospital. As part of their evaluation, the participants completed the incidental learning tasks. We compared their incidental learning performance to their performance on traditional memory measures. Results:Incidental learning scores correlated strongly with scores on the California Verbal Learning Test–Second Edition (CVLT–II) and Brief Visuospatial Memory Test–Revised (BVMT–R). After we conducted a partial correlation that controlled for the effects of age, incidental learning correlated significantly with the CVLT–II Immediate Free Recall, CVLT–II Short-Delay Recall, CVLT–II Long-Delay Recall, and CVLT–II Yes/No Recognition Hits, and with the BVMT–R Delayed Recall and BVMT–R Recognition Discrimination Index. Conclusions:Our incidental learning procedures derived from subtests of the WAIS–IV Edition are an efficient and valid way of measuring memory. These tasks add minimally to testing time and capitalize on the semantic encoding that is inherent in completing the Similarities and Vocabulary subtests.

Emerging evidence for speeded alphabet printing as a measure of processing speed and working memory

Abstract Alphabet Printing (in the forward and backward order) is a brief and highly portable test with promise as a screening measure of processing speed and simple working memory, constructs which are only minimally assessed in many of the most commonly-used cognitive screening instruments. The aim of this project was to examine the construct validity of timed Alphabet Printing in a sample of 254 Veterans with cognitive complaints and a history of possible head injury. Criterion measures included more established tests of processing speed and simple working memory, including the Trail Making Test and the Digit Span subtest from the fourth edition of the Wechsler Adult Intelligence Scales. Alphabet Printing scores moderately correlated with the criterion measures of attention, working memory, and processing speed, and demonstrated acceptable classification accuracy in discriminating between individuals with and without evidence of cognitive impairment on Trails B. These findings provide additional support for the possible utility of including Alphabet Printing during cognitive screenings or as part of a larger neuropsychological test battery.

Development of a scale of executive functioning for the RBANS

ABSTRACT The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a cognitive battery that contains scales of several cognitive abilities, but no scale in the instrument is exclusively dedicated to executive functioning. Although the subtests allow for observation of executive-type errors, each error is of fairly low base rate, and healthy and clinical normative data are lacking on the frequency of these types of errors, making their significance difficult to interpret in isolation. The aim of this project was to create an RBANS executive errors scale (RBANS EE) with items comprised of qualitatively dysexecutive errors committed throughout the test. Participants included Veterans referred for outpatient neuropsychological testing. Items were initially selected based on theoretical literature and were retained based on item-total correlations. The RBANS EE (a percentage calculated by dividing the number of dysexecutive errors by the total number of responses) was moderately related to each of seven established measures of executive functioning and was strongly predictive of dichotomous classification of executive impairment. Thus, the scale had solid concurrent validity, justifying its use as a supplementary scale. The RBANS EE requires no additional administration time and can provide a quantified measure of otherwise unmeasured aspects of executive functioning.