Influence of poor effort on self-reported symptoms and neurocognitive test performance following mild traumatic brain injury

Abstract

When considering a diagnosis of postconcussion syndrome, clinicians must systematically evaluate and eliminate the possible contribution of many differential diagnoses, comorbidities, and factors that may cause or maintain self-reported symptoms long after mild traumatic brain injury (MTBI). One potentially significant contributing factor is symptom exaggeration. The purpose of the study is to examine the influence of poor effort on self-reported symptoms (postconcussion symptoms and cognitive complaints) and neurocognitive test performance following MTBI. The MTBI sample consisted of 63 referrals to a concussion clinic, evaluated within 5 months post injury (M = 2.0, SD = 1.0, range = 0.6-4.6), who were receiving financial compensation from the Workers' Compensation Board. Participants completed the Post-Concussion Scale (PCS), British Columbia Cognitive Complaints Inventory (BC-CCI), selected tests from the Neuropsychological Assessment Battery Screening Module (S-NAB), and the Test of Memory Malingering (TOMM). Participants were divided into two groups based on TOMM performance (15 fail, 48 pass). There were significant main effects and large effect sizes for the PCS (p = .002, d = 0.79) and BC-CCI (p = .011, d = 0.98) total scores. Patients in the TOMM fail group scored higher than those in the TOMM pass group on both measures. Similarly, there were significant main effects and/or large effect sizes on the S-NAB. Patients in the TOMM fail group performed more poorly on the Attention (p = .004, d = 1.26), Memory (p = .006, d = 1.16), and Executive Functioning (p > .05, d = 0.70) indexes. These results highlight the importance of considering the influence of poor effort, in conjunction with a growing list of factors that can influence, maintain, and/or mimic the persistent postconcussion syndrome.

Postconcussive Symptom Exaggeration After Pediatric Mild Traumatic Brain Injury

“…52 In adults after mTBI, ∼50% of the variance in neuropsychological abilitybased test performance is accounted for by whether examinees exert adequate effort as measured by PVTs. [53][54][55][56] We found that nearly 40% of the abilitybased variance was accounted for by PVT performance in children after mTBI, 57 supporting the idea that some of the cognitive effects that are attributed to pediatric mTBI in clinical and research contexts are likely better explained by noncredible effort.…”

“…55,58,59 Even after controlling for other factors that influenced symptom reporting in this sample (eg, female gender, premorbid anxiety/depression, time since injury), MSVT performance remained a robust unique predictor of the level of endorsed symptomatology.…”

“…55,58,59 No identified pediatric study has examined the relationship between PVT performance and postconcussive symptoms. The current study was designed to examine the relationship between PVT failure and self-reported symptoms in a pediatric mTBI sample.…”

“…Although it is possible that certain children failed the MSVT but still provided valid symptom reports, we believe this is fairly unlikely in most cases given that a strong relationship exists between invalid performance-based test data and invalid self-report data in comparable adult studies. 55,58,59,[69][70][71] Pediatricians and other primary care providers often manage youth after mTBI, although many do not feel they have adequate training or the tools to care for these patients. 72 Primary care management of mTBI is complicated further by the present findings.…”

Perceived Social Support and Its Impact on Mental Fatigue in Patients with Mild Traumatic Brain Injury

“…In a randomized controlled trial, early individual intervention by a qualified rehabilitation team didn't appear to improve the outcome of one year after injury among persons with MTBI-related fatigue (10), nor after 10 years (11). Moreover, some studies indicated that intervention focusing on post-concussion symptoms (PCS) might in fact increase the awareness of PCS-like symptoms among subjects exposed to such injuries (12). Currently, there remains a dearth of evidence regarding the appropriate management of subjects with long-term post-MTBI fatigue.…”