PCS, Iatrogenic Symptoms, and Malingering Following Concussion

The Importance of the Morel Emotional Numbing Test Instructions: A Diagnosis Threat Induction Study

OBJECTIVE

Marketed as a validity test that detects feigning of posttraumatic stress disorder (PTSD), the Morel Emotional Numbing Test for PTSD (MENT) instructs examinees that PTSD may negatively affect performance on the measure. This study explored the potential that MENT performance depends on inclusion of "PTSD" in its instructions and the nature of the MENT as a performance validity versus a symptom validity test (PVT/SVT).

METHOD

358 participants completed the MENT as a part of a clinical neuropsychological evaluation. Participants were either administered the MENT with the standard instructions (SIs) that referenced "PTSD" or revised instructions (RIs) that did not. Others were administered instructions that referenced "ADHD" rather than PTSD (AI). Comparisons were conducted on those who presented with concerns for potential traumatic-stress related symptoms (SI vs. RI-1) or attention deficit (AI vs. RI-2).

RESULTS

Participants in either the SI or AI condition produced more MENT errors than those in their respective RI conditions. The relationship between MENT errors and other S/PVTs was significantly stronger in the SI: RI-1 comparison, such that errors correlated with self-reported trauma-related symptoms in the SI but not RI-1 condition. MENT failure also predicted PVT failure at nearly four times the rate of SVT failure.

CONCLUSIONS

Findings suggest that the MENT relies on overt reference to PTSD in its instructions, which is linked to the growing body of literature on "diagnosis threat" effects. The MENT may be considered a measure of suggestibility. Ethical considerations are discussed, as are the construct(s) measured by PVTs versus SVTs.

Characterizing the Network Structure of Post-Concussion Symptoms

OBJECTIVE

Assessment of post-concussion symptoms is implemented at secondary, post-secondary, and professional levels of athletics. Network theory suggests that disorders can be viewed as a set of interacting symptoms that amplify, reinforce, and maintain one another. Examining the network structure of post-concussion symptoms may provide new insights into symptom comorbidity and may inform targeted treatment. We used network analysis to examine the topology of post-concussion symptoms using the Post-Concussion Symptom Scale (PCSS) in high school athletes with recent suspected sport-related concussion.

METHOD

Using a cross-sectional design, the network was estimated from Post Concussion Symptom Scale scores from 3,292 high school athletes, where nodes represented symptoms and edges represented the association between symptoms. Node centrality was calculated to determine the relative importance of each symptom in the network.

RESULTS

The network consisted of edges within and across symptom domains. "Difficulty concentrating" and "dizziness" were the most central symptoms in the network. Although not highly central in the network, headaches were the highest rated symptom.

CONCLUSIONS

The interconnectedness among symptoms supports the notion that post-concussion symptoms are interrelated and mutually reinforcing. Given their central role in the network, "difficulty concentrating" and "dizziness" are expected to affect the activation and persistence of other post-concussion symptoms. Interventions targeting difficulties with concentration and dizziness may help alleviate other symptoms. Our findings could inform the development of targeted treatment with the aim of reducing overall symptom burden. Future research should examine the trajectory of post-concussion symptom networks to advance the clinical understanding of post-concussive recovery.

Improving Outcomes for Work-Related Concussions: A Mental Health Screening and Brief Therapy Model

OBJECTIVE

This study assessed the efficacy of a neurocognitive screening evaluation and brief therapy model to improve RTW outcomes for workers who experienced mild head injuries.

METHODS

Patients referred were evaluated using a neurocognitive and psychological screening battery. Work-focused cognitive behavioral therapy was provided when appropriate, addressing the role of negative emotional adjustment and functional sleep disturbance in prolonging recovery.

RESULTS

Average time to RTW was 7 weeks post-evaluation, despite workers being off an average of 10 months between injury and referral dates. Overall, 99% were released to full-duty work without restrictions or accommodations.

CONCLUSIONS

This study demonstrates the favorable outcomes achieved via a structured, clinically driven program for workers who experience head-involved injuries, validating previous research on the importance of recognizing the role of psychological factors in prolonging concussion recovery.

American Academy of Clinical Neuropsychology (AACN) 2021 consensus statement on validity assessment: Update of the 2009 AACN consensus conference statement on neuropsychological assessment of effort, response bias, and malingering

Objective: Citation and download data pertaining to the 2009 AACN consensus statement on validity assessment indicated that the topic maintained high interest in subsequent years, during which key terminology evolved and relevant empirical research proliferated. With a general goal of providing current guidance to the clinical neuropsychology community regarding this important topic, the specific update goals were to: identify current key definitions of terms relevant to validity assessment; learn what experts believe should be reaffirmed from the original consensus paper, as well as new consensus points; and incorporate the latest recommendations regarding the use of validity testing, as well as current application of the term 'malingering.' Methods: In the spring of 2019, four of the original 2009 work group chairs and additional experts for each work group were impaneled. A total of 20 individuals shared ideas and writing drafts until reaching consensus on January 21, 2021. Results: Consensus was reached regarding affirmation of prior salient points that continue to garner clinical and scientific support, as well as creation of new points. The resulting consensus statement addresses definitions and differential diagnosis, performance and symptom validity assessment, and research design and statistical issues. Conclusions/Importance: In order to provide bases for diagnoses and interpretations, the current consensus is that all clinical and forensic evaluations must proactively address the degree to which results of neuropsychological and psychological testing are valid. There is a strong and continually-growing evidence-based literature on which practitioners can confidently base their judgments regarding the selection and interpretation of validity measures.

Verifiability and Symptom Endorsement in Genuine, Exaggerated, and Malingered Pain

The current study has investigated whether pure malingering, in which reported symptoms are nonexistent, partial malingering, in which existent symptoms are exaggerated, and genuine symptoms could be differentiated by applying the verifiability approach (VA) and the Self-Report Symptom Inventory (SRSI). The logic behind the VA is that deceivers’ statements contain more non-verifiable information, whereas truth tellers’ accounts include more verifiable details. The SRSI taps into over-reporting by including a mix of genuine symptoms and implausible complaints (pseudosymptoms). We checked if participants (N = 167) allocated to one of three conditions (pure malingerers vs. exaggerators vs. truth tellers) can be differentiated in their pain symptom reports’ (non)verifiability and symptom endorsement. Findings revealed that deceptive reports were lengthier than truthful statements. However, this difference was not produced by a discrepancy in non-verifiable details, but rather by a higher production of verifiable information among malingerers and exaggerators. Thus, contrary to previous findings, our results indicate that pain reports rich in verifiable information should raise doubt about their veracity. Further, truth tellers endorsed less symptoms of the SRSI than exaggerators, but not than pure malingerers. Pure malingerers and exaggerators did not differ in symptom endorsement. Thus, our findings revealed that when compared with truth tellers, exaggerators exhibited stronger over-reporting tendencies than (pure) malingerers. However, due to inconsistent findings, further investigation of the efficacy of these methods in differentiation between exaggerated and malingered reports is required.

Persistent post-concussive symptoms: A model of predisposing, precipitating, and perpetuating factors

While the majority of individuals make full recovery within a short period following mild traumatic brain injury (mTBI), some continue to experience a more chronic course of symptoms termed persistent post-concussive symptoms (PPCS). Previous models and conceptualizations of PPCS have typically not differentiated the time at which factors present across the injury timeline spectrum or have considered a limited array of contributory factors. In the current review, PPCS are examined within the predisposing, precipitating, and perpetuating (PPP) model, which has been applied to explain other syndromes resulting in a clear framework to explain, disseminate, and further research the specified condition. Previous PPCS models are reviewed and integrated into this comprehensive model, as well. To do so, a literature review was completed which included previous PPP models applied to other conditions, other PPCS models, and more recent findings of factors related to PPCS. This new iteration and application of the PPP model more clearly, completely, and validly identifies contributing factors to PPCS. Future prevention, early identification, clearer questions for future research, and treatment of PPCS is possible with clarity provided by this model.

Validity Assessment in Traumatic Brain Injury Impairment and Disability Evaluations

This article provides an overview of validity assessment in persons with traumatic brain injury including evaluation caveats. Specific discussion is provided on post-concussive disorders, malingering, examination techniques to assess for validity, response bias, effort and non-organic/functional presentations. Examinee and examiner biases issues will also be explored. Discussion is also provided regarding judicial trends in limiting examiner scope of testing and/or testimony, and risk of liability when providing expert witness opinions on validity of examinee presentations. The hope is to encourage physiatrists to become more aware and skilled in validity assessment given its importance in differential diagnosis of impairment following traumatic brain injury.

Comprehensive analysis of the predictors of neurobehavioral symptom reporting in veterans

OBJECTIVE

This study assessed the strength of military-related concussion-, psychological-, and behavioral-related measures to predict neurobehavioral symptom (NBS) reporting in order to help clarify the extent to which persistent NBS reflect lingering effects of concussion vs other psychological/behavioral factors among veterans.

METHODS

Baseline analysis included 351 consecutively enrolled veterans in the Translational Research Center for Traumatic Brain Injury and Stress Disorders longitudinal cohort study. One hundred eighty-six returned for a follow-up evaluation averaging 24 months post baseline. The Neurobehavioral Symptom Inventory (NSI) was used to measure NBS reporting. Predictor variables included diagnosis of military-related mild traumatic brain injury (M-mTBI), psychological measures, including posttraumatic stress disorder, mood, anxiety, and substance abuse disorders, and behavioral measures, including self-reported current pain and sleep impairment. Hierarchical and multivariable regression analyses examined the relationships between the predictor variables and NSI scores. The k-fold cross-validation assessed generalizability and validity of the regressions.

RESULTS

Baseline analysis revealed that psychological and behavioral conditions independently accounted for 42.5% of variance in the NSI total score compared to 1.5% for M-mTBI after controlling for psychological and behavioral conditions. Prospective analysis revealed that M-mTBI at baseline did not significantly predict NSI score at follow-up, while psychological and behavioral measures at baseline independently accounted for 24.5% of NSI variance. Posttraumatic stress disorder was the most consistent predictor. Cross-validation analyses supported generalizability of the results.

CONCLUSIONS

Psychological and behavioral-related measures are strong predictors of persistent NBS reporting in veterans, while M-mTBI is negligible. NBS more likely reflect influential comorbidities as opposed to brain injury, per se.

Factitious disorders and malingering in relation to functional neurologic disorders

Interest in malingering has grown in recent years, and is reflected in the exponential increase in academic publications since 1990. Although malingering is more commonly detected in medicolegal practice, it is not an all-or-nothing presentation and moreover can vary in the extent of presentation. As a nonmedical disorder, the challenge for clinical practice remains that malingering by definition is intentional and deliberate. As such, clinical skills alone are often insufficient to detect it and we describe psychometric tests such as symptom validity tests and relevant nonmedical investigations. Finally, we describe those areas of neurologic practice where symptom exaggeration and deception are more likely to occur, e.g., postconcussional syndrome, psychogenic nonepileptic seizures, motor weakness and movement disorders, and chronic pain. Factitious disorders are rare in clinical practice and their detection depends largely on the level of clinical suspicion supported by the systematic collection of relevant information from a variety of sources. In this chapter we challenge the accepted DSM-5 definition of factitious disorder and suggest that the traditional glossaries have neglected the extent to which a person's reported symptoms can be considered a product of intentional choice or selective psychopathology largely beyond the subject's voluntary control, or more likely, both. We present evidence to suggest that neurologists preferentially diagnose factitious presentations in healthcare workers as "hysterical," possibly to avoid the stigma of simulated illness.