Research Letter: Long-Term Outcomes Following Cognitive Rehabilitation for Mild Traumatic Brain Injury: A 5-Year Follow-Up of a Cohort From the SCORE Randomized Clinical Trial.

OBJECTIVE: To examine the functioning of military service members 5 years after completing a randomized controlled trial (RCT) of cognitive rehabilitation for mild traumatic brain injury (mTBI). SETTING: Home-based telephonic interview and internet-based self-ratings. PARTICIPANTS: Sixty-nine of the 126 (55%) active-duty service members who were enrolled in a 4-arm RCT of cognitive rehabilitation 3 to 24 months after mTBI and were successfully contacted by phone 5 years later. Original and 5-year follow-up participants in each of 4 RCT treatment arms included: psychoeducation ( n = 32 original, n = 17 follow-up), computer ( n = 30 original, n = 11 follow-up), therapist-directed ( n = 30 original, n = 23 follow-up), integrated ( n = 34 original, n = 18 follow-up). DESIGN: Inception cohort evaluated 5 years after completion of an RCT of cognitive rehabilitation. MAIN MEASURES: Postconcussion symptoms (Neurobehavioral Symptom Inventory total score), psychological distress (Symptom Checklist-90-revised Global Severity Index score), and functional cognitive/behavioral symptoms (Key Behaviors Change Inventory total average score). RESULTS: Participants' postconcussive symptoms and psychological distress improved at the 5-year follow-up. Functional cognitive/behavioral symptoms were not significantly improved, but therapeutic gains were maintained across time, to 5 years after completing the RCT. CONCLUSION: In this sample of military personnel, postconcussive symptoms and psychological distress significantly improved from posttreatment to 5 years after cognitive rehabilitation, regardless of treatment arm. Functional cognitive/behavioral symptoms significantly improved with treatment while treatment gains were maintained at the 5-year follow-up. Replication of these results with a larger sample and interim data between 18 weeks and 5 years post-treatment is needed.

Number of Concussions Does Not Affect Treatment Response to Cognitive Rehabilitation Interventions Following Mild TBI in Military Service Members.

OBJECTIVE: The study objective was to determine whether number of concussions would affect symptom improvement following cognitive rehabilitation (CR) interventions. METHOD: Service members (N = 126) with concussion history completed a 6-week randomized control trial of CR interventions. Participants were stratified based on self-reported lifetime concussion frequency. Outcome measures included the Paced Auditory Serial Addition Test (PASAT), the Global Severity Index (GSI) from the Symptom Checklist-90-Revised, and the Key Behaviors Change Inventory (KBCI). RESULTS: Mixed-model analyses of variance revealed a significant main effect for time on cognitive, psychological, and neurobehavioral functioning. A significant main effect for the number of concussions was observed for GSI and KBCI, but not PASAT. Interactions between the number of concussions and time were not significant for any of the outcome variables. CONCLUSIONS: Over the 6-week interval, improvements were found for all participants across all outcome measures. Number of concussions did not affect improvements over time.

Weak associations between depressive symptom severity, depressive symptom clusters, and cognitive performance in young to middle-aged men without clinical depression.

Evidence suggests different depressive symptoms are related to  specific aspects of cognition, especially in older adults. The current study extended this literature by examining depressive symptom severity, symptom clusters, and cognitive functioning in young-to-middle aged adults. A sample of 2,560 men (mean age = 38.12 ± 2.41 years) withvalid Minnesota Multiphasic Personality Inventories (MMPI) and completed cognitive measures was drawn from a Vietnam veterans study. Bootstrapped regressions examined relationships between cognitive performance, MMPI Depression  scores, and Harris-Lingoes depression subscales after covariate adjustments. Follow-up analyses investigated non-elevated and elevated depressive symptom groups. We found inverse relationships between specific subscales (Subjective Depression and Mental Dullness) and attentional control. No significant relationships were evident for total depressive symptoms or for the group analyses. Findings suggest weak associations between depressive symptoms and cognition in young to middle-aged men without clinical depression, which adds to the literature on inconsistent findings in depressive symptom-cognition relationships.

Self-efficacy predicts response to cognitive rehabilitation in military service members with post-concussive symptoms.

This study examined whether self-efficacy differentiated treatment responders from non-responders in a trial of cognitive rehabilitation (CR) for postconcussive symptoms. 126 service members with mild TBI seen on average 9.5 months since injury completed one of four cognitive rehabilitation treatments for 6 weeks. The four treatment arms were: (1) Psychoeducation control, (2) Self-administered computerized CR, (3) Interdisciplinary CR, and (4) Interdisciplinary CR integrated with CBT. Outcome was assessed across time (baseline, and 6, 12, and 18 weeks post-treatment) for three domains: psychological (Symptom Checklist-90-Revised; SCL-90-R), cognitive (Paced Auditory Serial Addition Test; PASAT), and functional/behavioural (Key Behaviors Change Inventory; KBCI). Mixed model ANOVAs tested for self-efficacy differences across time in treatment responders versus non-responders, as defined by reliable change indices. A significant interaction was found on the SCL-90 such that responders had increasing self-efficacy with respect to psychological symptoms across four time points, whereas non-responders' self-efficacy did not change. Perceived self-efficacy at the beginning of treatment was associated with treatment engagement within the psychological domain for responders only, suggesting a mediating role in treatment outcome. Overall, results suggest that increasing patients' level of self-efficacy may be important for successful treatment of psychological distress in those with remote concussion.

A model for intervening with veterans and service members who are concerned about developing Chronic Traumatic Encephalopathy (CTE).

OBJECTIVE: This paper briefly reviews what is unknown about chronic traumatic encephalopathy (CTE), highlights understandable concerns by individuals with a history of mild traumatic brain injuries who present to neuropsychologists with fears about a deteriorating course and eventual dementia due to CTE, and proposes a three-phased model for intervening with such individuals. METHOD: The proposed model includes three phases - (1) assessment and education, (2) targeted interventions for specific symptoms and comorbidities (e.g., sleep disturbance, headache, depression), and (3) psychotherapy to address mental health issues. While this is generally the order in which they will occur, the approach is not necessarily linear but rather provides a recommended schema. CONCLUSION: Media attention on concussion has greatly increased in the last several years, as interest in the possible contribution of concussion(s) to CTE grows. This media attention has some adverse effects in that it creates a false perception about the current state of the science and may engender iatrogenic effects. The proposed model is offered as one approach to engage patients within this context.

Neuropsychological Characteristics of the Confusional State Following Traumatic Brain Injury.

OBJECTIVES: Individuals with moderate-severe traumatic brain injury (TBI) experience a transitory state of impaired consciousness and confusion often called posttraumatic confusional state (PTCS). This study examined the neuropsychological profile of PTCS. METHODS: Neuropsychometric profiles of 349 individuals in the TBI Model Systems National Database were examined 4 weeks post-TBI (±2 weeks). The PTCS group was subdivided into Low (n=46) and High Performing PTCS (n=45) via median split on an orientation/amnesia measure, and compared to participants who had emerged from PTCS (n=258). Neuropsychological patterns were examined using multivariate analyses of variance and mixed model analyses of covariance. RESULTS: All groups were globally impaired, but severity differed across groups (F(40,506)=3.44; p<.001; ŋp 2 =.206). Rate of forgetting (memory consolidation) was impaired in all groups, but failed to differentiate them (F(4,684)=0.46; p=.762). In contrast, executive memory control was significantly more impaired in PTCS groups than the emerged group: Intrusion errors: F(2,343)=8.78; p<.001; ŋ p 2=.049; False positive recognition errors: F(2,343)=3.70; p<.05; ŋp 2=.021. However, non-memory executive control and other executive memory processes did not differentiate those in versus emerged from PTCS. CONCLUSIONS: Executive memory control deficits in the context of globally impaired cognition characterize PTCS. This pattern differentiates individuals in and emerged from PTCS during the acute recovery period following TBI. (JINS, 2019, 25, 302-313).

Reconceptualizing rehabilitation of individuals with chronic symptoms following mild traumatic brain injury.

PURPOSE/OBJECTIVE: Effective treatment for postconcussive symptoms (PCS) immediately following mild traumatic brain injury (mTBI) includes reassurance, support, education about mTBI, and symptom management. However, effective treatments for chronic postconcussive-like symptoms, particularly with mental health comorbidities, remain unclear. Research Method/Design: We conduct a critical review of the treatment literature for chronic PCS, present exemplar studies of two alternative treatment approaches (i.e., cognitive rehabilitation (CR) and psychotherapy with various cognitive-behavioral therapy (CBT) approaches) and compare their relative effectiveness, and examine other literature to compare treatment benefits of one approach over another. RESULTS: This review and comparisons found CBT approaches to be 5 to 6 times more potent in reducing chronic PCS than CR. CONCLUSIONS/IMPLICATIONS: Based on these findings we encourage rehabilitation professionals to "re-conceptualize" the factors that likely underlie chronic PCS and the most effective treatment for this condition. We propose that CBT interventions focusing on comorbid and underlying mental health issues should be an essential, not adjunctive, treatment approach for chronic PCS. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Predicting treatment response to cognitive rehabilitation in military service members with mild traumatic brain injury.

OBJECTIVE: Determine factors that affect responsiveness to cognitive rehabilitation (CR) interventions in service members (SMs) who sustained mild traumatic brain injury (mTBI). METHOD: 126 SMs with a history of mTBI 3 to 24 months postinjury participated in a randomized clinical trial of one of four, 6-week treatment arms: (a) psychoeducation, (b) computer-based CR, (c) therapist-directed manualized CR, and (d) therapist-directed CR integrated with cognitive-behavioral psychotherapy. Practice-adjusted reliable change scores (RCS) were calculated for the three primary outcome measures: Paced Auditory Serial Addition Test (PASAT), Symptom Checklist-90 Revised (SCL-90-R) Global Severity Index (GSI), and Key Behaviors Change Inventory (KBCI). Hierarchical logistic regression was used to predict RCS. Variables considered were: (a) demographic, (b) injury characteristics, (c) comorbid mental health conditions, (d) nonspecific treatment variables (i.e., team vs. no-team milieu), and (e) specific treatment elements. RESULTS: No predictor variables were associated with RCS improvements on the PASAT or the SCL-90-R. Comorbid depression (p < .02) and team-treatment milieu (p < .02) were associated with RCS improvement on the KBCI. Specific CR (ps > .65) and psychotherapy treatments (p > .26) were not associated with improvements on any outcome. There was evidence that self-administered computer CR was not only not beneficial, but negatively associated with cognitive and neurobehavioral improvement. CONCLUSIONS: Although reliable improvements were found on the PASAT and KBCI, no specific treatment intervention effects were found. Rather, comorbid depression and team-milieu treatment environment were associated with improvement, but only on the KBCI. Comorbid depression was associated with higher rates of improvement. (PsycINFO Database Record

Post-deployment Mental Health Screening: A Systematic Review of Current Evidence and Future Directions.

Population-based post-deployment screening programs within the Departments of Defense and Veterans Affairs have been implemented to assess for mental health conditions and traumatic brain injury. The purpose of this paper is to systematically review the literature on post-deployment screening within this context and evaluate evidence compared to commonly accepted screening implementation criteria. Findings reflected highly variable psychometric properties of the various screens, variable treatment referral rates following screening, low to moderate treatment initiation rates following screening, and no information on treatment completion or long-term outcomes following screening. In sum, the evidence supporting population based post-deployment screening is inconclusive. Implications are discussed.

Neuropsychological Performance and Subjective Symptom Reporting in Military Service Members With a History of Multiple Concussions: Comparison With a Single Concussion, Posttraumatic Stress Disorder, and Orthopedic Trauma.

OBJECTIVE: To examine differences in objective neurocognitive performance and subjective cognitive symptoms in individuals with a history of a single concussion, multiple concussions, orthopedic injuries, and posttraumatic stress disorder (PTSD). METHOD: Participants included 116 military service members who sustained a mild traumatic brain injury (mTBI) during combat deployment. Subjects were subdivided into groups based on concussion frequency: a single concussion (n = 42), 2 concussions (n = 21), and 3 or more concussions (n = 53). Eighty-one subjects sustained an orthopedic injury (n = 60) during deployment or were diagnosed with PTSD (n = 21), but had no history of mTBI. Subjects completed a battery of neuropsychological tests and self-report measures of postconcussive symptoms, PTSD symptoms, and psychopathology. RESULTS: No differences were found among the concussion groups on a composite neuropsychological measure. The PTSD group had the highest number of symptom complaints, with the 2-concussion and 3-plus-concussion groups being most similar to the PTSD group. The concussion groups showed a nonsignificant pattern of increasing distress with increasing number of concussions. CONCLUSIONS: The current findings are consistent with meta-analytic results showing no differential effect on neuropsychological functioning due to multiple concussions. Results also support the burden of adversity hypothesis suggesting increasing symptom levels with increasing psychological or physically traumatic exposures.

Comorbid Posttraumatic Stress Disorder and Traumatic Brain Injury: Generalization of Prolonged-Exposure PTSD Treatment Outcomes to Postconcussive Symptoms, Cognition, and Self-Efficacy in Veterans and Active Duty Service Members.

OBJECTIVES: To examine (a) generalization of the effectiveness of prolonged exposure (PE) therapy for posttraumatic stress disorder (PTSD) in improving postconcussive symptoms (PCSs) and other outcomes in military service members and Veterans (VA) with histories of mild to severe traumatic brain injury (TBI), and (b) factors associated with PCS reduction. SETTING: VA polytrauma medical center. PARTICIPANTS: Consecutive referrals for PTSD treatment of Active Duty (n = 17) or Veterans (n = 27) diagnosed with PTSD and TBI (N = 44). MAIN OUTCOME MEASURES: Neurobehavioral Symptom Inventory, Key Behaviors Change Inventory, Self-Efficacy for Symptom Management, Posttraumatic Stress Disorder Checklist, and Beck Depression Inventory, 2nd edition. DESIGN: Post hoc analysis of archival clinical effectiveness program evaluation data. INTERVENTIONS: PE for PTSD. RESULTS: There were significant improvements on all outcome measures with large effect sizes (Cohen's d ranging from 0.68 to 2.02). Improvement on PCS (Cohen's d = 1.21) was associated with lower levels of VA service-connected disability and PE treatment completion. CONCLUSION: PE treatment-related improvements for participants with comorbid PTSD and TBI generalize from PTSD outcomes to PCS and other TBI-related outcomes. Positive outcomes were independent of TBI severity, treatment setting, or Veteran status, but dependent upon PE treatment completion and lower levels of VA service-connected disability.

A Systems Science Approach to Understanding Polytrauma and Blast-Related Injury: Bayesian Network Model of Data From a Survey of the Florida National Guard.

We sought to further define the epidemiology of the complex, multiple injuries collectively known as polytrauma/blast-related injury (PT/BRI). Using a systems science approach, we performed Bayesian network modeling to find the most accurate representation of the complex system of PT/BRI and identify key variables for understanding the subsequent effects of blast exposure in a sample of Florida National Guard members (1,443 deployed to Operation Enduring Freedom/Operation Iraqi Freedom and 1,655 not deployed) who completed an online survey during the period from 2009 to 2010. We found that postdeployment symptoms reported as present at the time of the survey were largely independent of deployment per se. Blast exposure, not mild traumatic brain injury (TBI), acted as the primary military deployment-related driver of PT/BRI symptoms. Blast exposure was indirectly linked to mild TBI via other deployment-related traumas and was a significant risk for a high level of posttraumatic stress disorder (PTSD) arousal symptoms. PTSD arousal symptoms and tinnitus were directly dependent upon blast exposure, with both acting as bridge symptoms to other postdeployment mental health and physical symptoms, respectively. Neurobehavioral or postconcussion-like symptoms had no significant dependence relationship with mild TBI, but they were synergistic with blast exposure in influencing PTSD arousal symptoms. A replication of this analysis using a larger PT/BRI database is warranted.

Utility of the Neurobehavioral Symptom Inventory As an Outcome Measure: A VA TBI Model Systems Study.

OBJECTIVE: To examine the utility of the Neurobehavioral Symptom Inventory (NSI)-a measure of postconcussion symptoms used within the Veterans Health Administration-as an index of rehabilitation outcome. SETTING: Veterans Administration Polytrauma Rehabilitation Centers Traumatic Brain Injury (TBI) Model Systems program. PARTICIPANTS: A total of 159 Veterans (14% with mild TBI; 86% with moderate-severe TBI). MAIN MEASURES: Disability Rating Scale; Functional Independence Measure; Glasgow Outcome Scale-Extended; NSI; Participation Assessment with Recombined Tools-Objective; Posttraumatic Stress Disorder Checklist-Civilian Version; Satisfaction With Life Scale; Supervision Rating Scale. ANALYSES: Correlations and exploratory factor analyses examined the interrelations among outcome measures. Hierarchical regression analyses were utilized to determine if the NSI predicted rehabilitation outcome measures after controlling for demographic variables, TBI severity, and time since injury. NSI reliable changes from pretreatment to 1-year follow-up were examined. Receiver operating characteristics curve analyses were conducted to evaluate the ability of changes in the NSI to predict meaningful change in functioning and employment status. RESULTS: The NSI correlated with psychological distress measures. The NSI administered prior to brain injury rehabilitation had limited predictive utility beyond satisfaction with life. A minority of patients (32%) demonstrated reliable changes on the NSI from baseline to 1-year follow-up. Changes on the NSI were not predictive of meaningful change in employment or functioning. CONCLUSION: The NSI was not useful for assessing meaningful change in a sample of mixed severity TBI patients.

Cognitive Rehabilitation for Military Service Members With Mild Traumatic Brain Injury: A Randomized Clinical Trial.

OBJECTIVE: To compare cognitive rehabilitation (CR) interventions for mild traumatic brain injury (mTBI) with standard of care management, including psychoeducation and medical care for noncognitive symptoms. SETTING: Military medical center. PARTICIPANTS: A total of 126 service members who received mTBI from 3 to 24 months before baseline evaluation and reported ongoing cognitive difficulties. INTERVENTIONS: Randomized clinical trial with treatment outcomes assessed at baseline, 3-week, 6-week, 12-week, and 18-week follow-ups. Participants were randomly assigned to one of four 6-week treatment arms: (1) psychoeducation, (2) computer-based CR, (3) therapist-directed manualized CR, and (4) integrated therapist-directed CR combined with cognitive-behavioral psychotherapy (CBT). Treatment dosage was constant (10 h/wk) for intervention arms 2 to 4. MEASURES: Paced Auditory Serial Addition Test (PASAT); Symptom Checklist-90 Revised (SCL-90-R); Key Behaviors Change Inventory (KBCI). RESULTS: No differences were noted between treatment arms on demographics, injury-related characteristics, or psychiatric comorbidity apart from education, with participants assigned to the computer arm having less education. Using mixed-model analysis of variance, all 4 treatment groups showed a significant improvement over time on the 3 primary outcome measures. Treatment groups showed equivalent improvement on the PASAT. The therapist-directed CR and integrated CR treatment groups had better KBCI outcomes compared with the psychoeducation group. Improvements on primary outcome measures during treatment were maintained at follow-up with no differences among arms. CONCLUSIONS: Both therapist-directed CR and integrated CR with CBT reduced functional cognitive symptoms in service members after mTBI beyond psychoeducation and medical management alone.

Patient, Therapist, and System Factors Influencing the Effectiveness of Prolonged Exposure for Veterans With Comorbid Posttraumatic Stress Disorder and Traumatic Brain Injury.

In contrast to concerns that cognitive limitations and neurobehavioral symptoms (NBS) associated with traumatic brain injury (TBI) may inhibit treatment effectiveness, a recent study found prolonged exposure (PE) led to large reductions in posttraumatic stress disorder (PTSD) symptoms among Iraq-Afghanistan veterans with a range of TBI severity (article by Wolf, Kretzmer, Crawford, Thors, Wagner, Strom, Eftekhari, Klenk, Hayward, and Vanderploeg [J Trauma Stress 28:339-347, 2015]). We further examined this sample of 69 veterans to determine whether system, veteran, and therapist factors predicted clinically significant responses. Results of hierarchical, logistic regressions revealed that therapist training in PE and lower service connection were associated with increased odds of large decreases in PTSD symptoms after adjusting for the robust effect of PE sessions completed. Other patient-level factors including age, time since injury, and baseline NBS were unrelated to significant improvements. Findings emphasized the impact of PE dosage, indicated greater mastery of the protocol was beneficial, and showed that service connection could impede self-reported, clinically significant change during PE in this important cohort.

Variations in Inpatient Rehabilitation Functional Outcomes Across Centers in the Traumatic Brain Injury Model Systems Study and the Influence of Demographics and Injury Severity on Patient Outcomes.

OBJECTIVE: To compare patient functional outcomes across Traumatic Brain Injury Model Systems (TBIMS) rehabilitation centers using an enhanced statistical model and to determine factors that influence those outcomes. DESIGN: Multicenter observational cohort study. SETTING: TBIMS centers. PARTICIPANTS: Patients with traumatic brain injury (TBI) admitted to 19 TBIMS rehabilitation centers from 2003-2012 (N=5505). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Functional outcomes of patients with TBI. RESULTS: Individuals with lower functional status at the time of admission, longer duration of posttraumatic amnesia, and higher burden of medical comorbidities continued to have worse functional outcomes at discharge from inpatient rehabilitation and at the 1-year follow-up, whereas those who were employed at the time of injury had better outcomes at both time periods. Risk-adjusted patient functional outcomes for patients in most TBIMS centers were consistent with previous research. However, there were wide performance differences for a few centers even after using more recently collected data, improving on the regression models by adding predictors known to influence functional outcomes, and using bootstrapping to eliminate confounds. CONCLUSIONS: Specific patient, injury, and clinical factors are associated with differences in functional outcomes within and across TBIMS rehabilitation centers. However, these factors did not explain all the variance in patient outcomes, suggesting a role of some other predictors that remain unknown.

The role of performance validity tests in the assessment of cognitive functioning after military concussion: A replication and extension.

The current investigation is a replication and extension of a previously published study by Cooper, Vanderploeg, Armistead-Jehle, Lewis, and Bowles (2014) demonstrating that performance validity test scores accounted for more variance in cognitive testing among service members with a history of concussion than did demographic variables, etiology of and time since injury, and symptom severity. The present study included a sample of 142 active-duty service members evaluated following a suspected or confirmed history of mild traumatic brain injury. Participants completed a battery of neuropsychological measures that included scales of performance and symptom validity (specifically the Medical Symptom Validity Test, Nonverbal Medical Symptom Validity Test, and Personality Assessment Inventory). Among the factors considered in the current study, performance validity test results accounted for the most variance in cognitive test scores, above demographic, concussion history, symptom validity, and psychological distress variables. Performance validity test results were modestly related to symptom validity as measured by the Personality Assessment Inventory Negative Impression Management scale. In sum, the current results replicated the original Cooper et al. study and highlight the importance of including performance validity tests as part of neurocognitive evaluation, even in clinical contexts, within this population.

Screening for Remote History of Mild Traumatic Brain Injury in VHA: A Critical Literature Review.

OBJECTIVE: The authors reviewed the existing literature on the Veterans Health Administration's (VHA's) traumatic brain injury (TBI) screening and evaluation program to provide a qualitative synthesis and critical review of results focusing on the psychometric properties of the screen. METHODS: All studies of the VHA's screening and evaluation process were reviewed, both those involving primary data collection and those relying upon VHA data. Diagnostic statistics were summarized and also recalculated on the basis of a positive screening rate of 20%, the observed rate within the VHA, and an estimated population prevalence of TBI of 15% within the Department of Veterans Affairs (VHA). RESULTS: The TBI screen within the VHA is administered to nearly every eligible patient. The majority of clinical presentations are deemed to be due to mental health and/or a combination of mental health and TBI factors. The screen has good internal consistency, variable test-retest reliability, and questionable validity, with poor agreement between the TBI screen and criterion standards overall. Studies based on nonrepresentative samples reported high sensitivity. Assuming the VHA's TBI screening rate of 20% in a hypothetical sample, sensitivity is poor (the screen misses 30%-60% of TBI cases). However, specificity remains adequate. Studies based on samples with high rates of TBI reported much higher positive predictive values (and slightly lower negative predictive values) than those observed when a hypothetical TBI prevalence of 15% was used. CONCLUSION: Questions remain about the validity of the TBI screen. Future research should address the utility of screening for TBI.

Subconcussive Blows to the Head: A Formative Review of Short-term Clinical Outcomes.

BACKGROUND: Given questions about "lower thresholds" for concussion, as well as possible effects of repetitive concussion and chronic traumatic encephalopathy (CTE), and associated controversy, there is increasing interest in "subconcussive" blows and their potential significance. OBJECTIVE: A formative review with critical examination of the developing literature on subconcussive blows in athletes with an emphasis on clinical outcomes. METHODS: Studies of biomechanical, performance and/or symptom-based, and neuroimaging data were identified via PubMed search and critically reviewed. Five studies of symptom reporting/performance and 4 studies of neuroimaging were included. RESULTS: The relation between biomechanical parameters and diagnosed concussion is not straightforward (ie, it is not the case that greater and more force leads to more severe injury or cognitive/behavioral sequelae). Neuropsychological studies of subconcussive blows within a single athletic season have failed to demonstrate any strong and consistent relations between number and severity of subconcussive events and cognitive change. Recent studies using neuroimaging have demonstrated a potential cumulative effect of subconcussive blows, at least in a subset of individuals. CONCLUSION: Human studies of the neurological/neuropsychological impact of subconcussive blows are currently quite limited. Subconcussive blows, in the short-term, have not been shown to cause significant clinical effects. To date, findings suggest that any effect of subconcussive blows is likely to be small or nonexistent, perhaps evident in a subset of individuals on select measures, and maybe even beneficial in some cases. Longer-term prospective studies are needed to determine if there is a cumulative dose effect.

Development and Initial Validation of Military Deployment-Related TBI Quality-of-Life Item Banks.

OBJECTIVE: To investigate unique factors that affect health-related quality of life (QOL) in individuals with military deployment-related traumatic brain injury (MDR-TBI) and to develop appropriate assessment tools, consistent with the TBI-QOL/PROMIS/Neuro-QOL systems. PARTICIPANTS: Three focus groups from each of the 4 Veterans Administration (VA) Polytrauma Rehabilitation Centers, consisting of 20 veterans with mild to severe MDR-TBI, and 36 VA providers were involved in early stage of new item banks development. The item banks were field tested in a sample (N = 485) of veterans enrolled in VA and diagnosed with an MDR-TBI. DESIGN: Focus groups and survey. OUTCOME MEASURES: Developed item banks and short forms for Guilt, Posttraumatic Stress Disorder/Trauma, and Military-Related Loss. RESULTS: Three new item banks representing unique domains of MDR-TBI health outcomes were created: 15 new Posttraumatic Stress Disorder items plus 16 SCI-QOL legacy Trauma items, 37 new Military-Related Loss items plus 18 TBI-QOL legacy Grief/Loss items, and 33 new Guilt items. Exploratory and confirmatory factor analyses plus bifactor analysis of the items supported sufficient unidimensionality of the new item pools. Convergent and discriminant analyses results, as well as known group comparisons, provided initial support for the validity and clinical utility of the new item response theory-calibrated item banks and their short forms. CONCLUSION: This work provides a unique opportunity to identify issues specific to individuals with MDR-TBI and ensure that they are captured in QOL assessment, thus extending the existing TBI-QOL measurement system.