Mild Traumatic Brain Injury in the Maturing Brain: An Investigation of Symptoms and Cognitive Performance in Soldiers Returning From Afghanistan and Iraq.

OBJECTIVE: The majority of traumatic brain injuries (TBIs) are classified as mild and occur in young individuals. The course of recovery varies but can result in chronic or troubling outcomes. The impact of age on TBI outcomes in young adults before complete brain maturation is not well studied. METHODS: In this study, we compared the effects of mild TBI on cognitive performance and self-reported TBI symptoms and posttraumatic stress disorder (PTSD) in 903 soldiers in 3 different age groups: 24 years or younger, 25 to 27 years, and 28 to 40 years. The soldiers had returned from war zones in Iraq and were screened for TBI within a few days of return. Cognitive performance was measured with the Automated Neuropsychological Assessment Metrics of Military TBI Version 4 (ANAM4). Symptoms associated with mild TBI were self-reported on the Neurobehavioral Symptom Inventory, and the PTSD Checklist-Civilian Version (PCL-C). RESULTS: Soldiers with TBI in every age group had significantly higher prevalence of most symptoms than those with no TBI. Soldiers with TBI also reported more chronic pain sites, regardless of age. Soldiers aged 28 to 40 years with TBI had the lowest cognitive performance scores (ANAM) across several subtests, both unadjusted and adjusted. The Global Deficit Score was significantly higher for soldiers aged 28 to 40 years and 25 to 27 years with TBI than for soldiers younger than 24 years with no TBI. After adjusting for PTSD symptoms, education, and number of lifetime TBIs, the overall test battery mean for soldiers aged 28 to 40 years with TBI was significantly lower than for soldiers younger than 24 years with no TBI. CONCLUSION: Soldiers with mild TBI in the younger age group show more symptoms associated to frontal lobe function while soldiers in the older group suffer more cognitive impairment. This may warrant further study as it may indicate a propensity to later cognitive decline among soldiers who were older at the time of injury.

Role of Department of Defense Policies in Identifying Traumatic Brain Injuries Among Deployed US Service Members, 2001-2016.

OBJECTIVES: To examine the role of Department of Defense policies in identifying theater-sustained traumatic brain injuries (TBIs). METHODS: We conducted a retrospective study of 48 172 US military service members who sustained their first lifetime TBIs between 2001 and 2016 while deployed to Afghanistan or Iraq. We used multivariable negative binomial models to examine the changes in TBI incidence rates following the introduction of Department of Defense policies. RESULTS: Two Army policies encouraging TBI reporting were associated with an increase of 251% and 97% in TBIs identified following their implementation, respectively. Among airmen, the introduction of TBI-specific screening questions to the Post-Deployment Health Assessment was associated with a 78% increase in reported TBIs. The 2010 Department of Defense Directive Type Memorandum 09-033 was associated with another increase of 80% in the likelihood of being identified with a TBI among soldiers, a 51% increase among sailors, and a 124% increase among Marines. CONCLUSIONS: Department of Defense and service-specific policies introduced between 2006 and 2013 significantly increased the number of battlefield TBIs identified, successfully improving the longstanding problem of underreporting of TBIs.

A Clinical Evidence-Based Approach to Examine the Effects of mTBI and PTSD Symptoms on ANAM Performance in Recently Deployed Active Duty Soldiers: Results From the Warrior Strong Study.

OBJECTIVE: Service members are frequently diagnosed with comorbid mild traumatic brain injury (mTBI) and posttraumatic stress disorder after returning from Afghanistan and Iraq. Little is known about how mTBI in the postacute and chronic phases combined with current posttraumatic stress disorder symptoms (PTS) affects performance on the Automated Neuropsychological Assessment Metrics, Version 4, Traumatic Brain Injury-Military (ANAM4) battery used by the US military. We examined postdeployment ANAM4 performance using conventional statistical methods, as well as rates of poor performance, below established cutoffs (<10th and ≤2nd percentile). METHODS: A total of 868 soldiers were assessed for history of mTBI during the most recent deployment, as well as, lifetime mTBI, current PTS, and current pain-related symptoms. The ANAM4 was also administered. RESULTS: Soldiers with PTS and/or mTBI performed worse on ANAM4 relative to controls with those with both conditions performing worst. However, a nontrivial minority (∼10%-30%) of individuals with mTBI, PTS, or both had scores that were at or below the second percentile. CONCLUSION: Our results illustrate that a combination of mTBI and PTS is associated with worse ANAM4 performance than either condition alone. Furthermore, only a minority of soldiers with any, or both, of the conditions had ANAM deficits. The long-lasting impacts and unique contribution of each condition have yet to be determined.

Headache in military service members with a history of mild traumatic brain injury: A cohort study of diagnosis and classification.

Introduction Headaches after concussion are highly prevalent, relatively persistent and are being treated like primary headaches, especially migraine. Methods We studied all new patients seen between August 2008 and December 2009 assessed by a civilian headache specialist at the TBI Center at Womack Army Medical Center, Fort Bragg, NC. We report sample demographics, injuries and headache characteristics, including time from injury to headache onset, detailed descriptions and International Classification of Headache Disorders second edition primary headache diagnosis type. Results A total of 95 soldiers reported 166 headaches. The most common injury cited was a blast (53.7%). Most subjects (76.8%) recalled the onset of any headache within 7 days of injury. The most commonly diagnosed headache was a continuous type with migraine features ( n = 31 (18.7%)), followed by chronic migraine (type 1.5.1, n = 14 (8.4%)), migraine with aura (type 1.2.1, n = 10 (6.0%)), hemicrania continua (type 4.7, n = 12 (7.2%)), chronic cluster (type 3.1.2, n = 6 (3.6%)) and headaches not otherwise classifiable (type 14.1, n = 5 (3.0%)) also present. The most clinically important was a continuous headache with migraine features. Conclusion We present a series of patients seen in a military treatment facility for headache diagnosis after concussion in whom we found migraine, as well as uncommon primary headache types, at frequencies that were much higher than expected.

Which Matters More? A Retrospective Cohort Study of Headache Characteristics and Diagnosis Type in Soldiers with mTBI/Concussion.

OBJECTIVE: To describe the diagnostic types and characteristics of headaches in soldiers with mild traumatic brain injury during the wars in Afghanistan and Iraq. BACKGROUND: Persistent post-traumatic headache interferes with returns to activity or duty. The most commonly cited headache diagnosis after concussion is migraine. We hypothesize that headache diagnosis type, eg, migraine, is not sufficient to predict relationships with occupational outcomes after concussion. METHODS: The study sample consisted of all new patients referred for headache evaluation at the Brain Injury Center at Womack Army Medical Center over a 1-year time period. The design was retrospective and observational. Clinical data reported included demographics, causes of injury, headache characteristics, and headache diagnosis type. After reviewing records for retention or severance from military service, the primary occupational outcome measure was departure from service due to medical cause as determined by a Medical Evaluation Board (MEB). The primary outcome measure was to test the strength of association between leaving service for MEB and headache characteristics or diagnosis. RESULTS: A total of 95 patients (94% male) with concussion described 166 distinct headache types, the most common being migraine (60%) and trigeminal autonomic cephalalgia (24%). A total of 25% of all patients remained on active duty. A continuous headache of any type was present in 75% of patients and of these, 23% remained on active duty. Of the 51% of patients who had both a continuous and non-continuous headache, 17% remained on active duty (P < .001). Therefore, we report that a continuous headache, regardless of diagnosis type was associated with negative occupational outcomes. Regardless of headache duration, headache diagnosis type alone was not associated with soldiers' separations from service. CONCLUSIONS: Persistent post-traumatic headache is most likely to present with continuous pain. Migraine is the most common primary diagnosis type. The presence of a continuous headache was strongly associated with negative occupational outcomes. Primary headache diagnosis type was not. Headache characteristics, therefore, may be more important than diagnosis type when determining active duty status. Further prospective research is indicated.

Military Deployment May Increase the Risk for Traumatic Brain Injury Following Deployment.

OBJECTIVE: To compare rates of traumatic brain injury (TBI) diagnosis before and after overseas military deployment. DESIGN: We conducted a retrospective examination of a cohort of 119 353 active duty US military service members (Army, Navy, Air Force, and Marines) whose first lifetime overseas deployment began at any time between January 1, 2011, and December 31, 2011, and lasted at least for 30 days. For this cohort, TBI diagnoses were examined during the 76 weeks prior to deployment, during deployment, and 76 weeks following the end of deployment. MAIN MEASURES: 4-week rates of TBI diagnosis. RESULTS: The risk of being diagnosed with TBI within 4 weeks after returning from deployment was 8.4 times higher than the average risk before deployment. The risk gradually decreased thereafter up to 40 weeks postdeployment. However, during the 41 to 76 weeks following deployment, risk stabilized but remained on average 1.7 times higher than before deployment. CONCLUSION: An increased rate of TBI diagnosis following deployment was identified, which may be partly due to delayed diagnosis of TBIs that occurred while service members were deployed. Also, the increased rate may partly be due to riskier behaviors of service members following deployment that results in an increased occurrence of TBIs.

The experience, expression, and control of anger following traumatic brain injury in a military sample.

OBJECTIVE: To investigate the impact of traumatic brain injury (TBI) on the experience and expression of anger in a military sample. PARTICIPANTS: A total of 661 military personnel with a history of TBI and 1204 military personnel with no history of TBI. DESIGN: Cross-sectional, between-group design, using multivariate analysis of variance. MAIN MEASURE: State-Trait Anger Expression Inventory-2 (STAXI-2). RESULTS: Participants with a history of TBI had higher scores on the STAXI-2 than controls and were 2 to 3 times more likely than the participants in the control group to have at least 1 clinically significant elevation on the STAXI-2. Results suggested that greater time since injury (ie, months between TBI and assessment) was associated with lower scores on the STAXI-2 State Anger scale. CONCLUSION: Although the results do not take into account confounding psychiatric conditions and cannot address causality, they suggest that a history of TBI increases the risk of problems with the experience, expression, and control of anger. This bolsters the need for proper assessment of anger when evaluating TBI in a military cohort.

Accuracy of Reaction Time Measurement on Automated Neuropsychological Assessment Metric UltraMobile.

OBJECTIVE: This observational study examined the accuracy of simple reaction time (RT) measurements on various touchscreen tablet devices using the Automated Neuropsychological Assessment Metric (ANAM) UltraMobile test battery. The study investigated the implications of interpreting ANAM UltraMobile with laptop-based normative data by analyzing the magnitude and variability of RT accuracy across devices. METHOD: RT accuracy on 10 different tablets was assessed using a photodetector and robotic arm to respond to stimuli at predetermined response times. The recorded RT was compared with the true RT obtained from the robotic arm to calculate the RT error. RESULTS: ANAM UltraMobile recorded slower RTs than the laptop version. Additionally, RT error varied considerably among the 10 tablet models, suggesting psychometrically significant implications that could lead to interpretive errors when using laptop-based normative data. CONCLUSIONS: Relative to the RT error from the laptop-based version of ANAM, tablet data from ANAM UltraMobile are significantly slower and exhibit large variability between devices. These differences may have clinically significant implications for the comparability of the two versions. The findings suggest that further research with human participants is needed to assess the equivalence of ANAM UltraMobile with its predecessor.

Longitudinal health outcomes in caregivers of military members with traumatic brain injury.

PURPOSE/OBJECTIVE: To examine longitudinal change in health-related quality of life (HRQOL) in caregivers of service members/veterans with traumatic brain injury and factors associated with clinically elevated symptoms. RESEARCH METHOD/DESIGN: Caregivers (N = 220) completed nine HRQOL outcome measures and 10 risk factor measures at a baseline evaluation and follow-up evaluation 3 years later. Caregiver's responses on the nine HRQOL outcome measures were classified into four clinical change categories based on the presence/absence of clinically elevated T-scores (≥ 60 T) at baseline and follow-up: (a) Persistent (baseline ≥ 60T + follow-up ≥ 60 T), (b) Developed (baseline < 60 T + follow-up ≥ 60 T), (c) Improved (baseline ≥ 60 T + follow-up < 60 T), and (d) Asymptomatic (baseline < 60 T + follow-up < 60 T). A clinical change composite score was calculated by summing the number of Persistent or Developed HRQOL outcome measures and used to create three clinical change groups: (a) No Symptoms (n = 69, zero measures), (b) Some Symptoms (n = 88, one to three measures), and (c) Numerous Symptoms (n = 63, four to nine measures). RESULTS: Of the nine HRQOL outcome measures, Bodily Pain, Perceived Stress, Sleep-Related Impairment, and Fatigue were most frequently classified as Persistent or Developed from baseline to follow-up in the entire sample. A linear relationship was found between the vast majority of risk factors across the three clinical change groups at baseline and follow-up (Numerous > Some > None). The risk factors were correlated with the number of elevated HRQOL symptoms at baseline and follow-up. Most Asymptomatic or Persistent caregivers did not have meaningful change (≥ 1 SD) in HRQOL scores. A sizable proportion of Developed or Improved caregivers had either meaningful or no change in HRQOL scores. CONCLUSIONS/IMPLICATIONS: There is a need for ongoing clinical services for military caregivers. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Family caregivers of service members in United States Department of Defense health care report impairment in longitudinal health outcomes.

OBJECTIVE: To examine elevated symptoms on health-related quality of life (HRQOL) measures over 2 years in caregivers of service members with traumatic brain injury (TBI). To compare outcomes to caregivers of veterans. METHOD: Caregivers (N = 315) were classified into two groups: (a) service member caregiver group (n = 55) and (b) veteran caregiver group (n = 260). Caregivers completed 17 HRQOL measures at a baseline evaluation and follow-up evaluation 24 months later. RESULTS: In the service member caregiver group, the highest frequency of clinically elevated T-scores (≥ 60 T) at baseline and follow-up were found on physical and psychological HRQOL measures (16.4%-30.9%). A higher proportion of the veteran caregiver group had clinically elevated scores on nine measures at baseline and seven measures at follow-up. Examining the number of clinically elevated scores simultaneously across all 17 measures, the service member caregiver group had multiple elevated scores (e.g., 4 or more: baseline = 25.5%, follow-up = 27.3%). A higher proportion of the veteran caregiver group had multiple clinically elevated scores for 13 comparisons at baseline (h = .35-.82), but reduced to eight comparisons at follow-up (h = .36-.63). In the service member caregiver group, the proportion of caregivers with clinically elevated scores at baseline and follow-up was equally dispersed across persistent and newly developed symptoms, but higher for persistent symptoms compared to developed symptoms in the veteran caregiver group. CONCLUSIONS: Many caregivers of service members reported clinically elevated scores across HRQOL domains and the prevalence increased over 2 years. More services for caregivers in the Department of Defense may be helpful in reducing the trajectory of newly developed symptoms long term. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

The Patient Global Impression of Change as a complementary tool to account for neurobehavioral and mental health symptom improvement for patients with concussion.

PURPOSE: The purpose of this study was to determine the extent to which patient's perspective of symptom improvement, as indexed by the Patient Global Impression of Change (PGIC) survey, is associated with symptom improvement on common measures of neurobehavioral and mental health symptoms following concussion. MATERIALS AND METHODS: Data were from 449 US active duty service members receiving treatment in interdisciplinary programs for their concussion. PGIC rating (range = 1-7) was evaluated for compatibility in assessing improvement in or clinically-elevated neurobehavioral (using Neurobehavioral Symptom Inventory [NSI]) and mental health (using Post-traumatic Stress Disorder Checklist, DSM-5 [PCL-5] and Patient Health Questionnaire [PHQ-8]) symptoms. RESULTS: Higher PGIC scores were related to a higher prevalence of clinically-relevant decrease in NSI, PCL-5 or PHQ-8 scores. Participants with a PGIC rating of 3+ (vs.<3) were about 2.2 (CI = 1.4-3.5), 1.6 (CI = 1.1-1.3), and 2.7 (CI = 1.4-5.1) times more likely to report clinically-relevant decrease in NSI, PCL-5 and PHQ-8 symptoms, respectively. CONCLUSION: PGIC may help providers incorporate patients' perspectives on symptom improvement achieved during rehabilitation. An approach combining PGIC with surveys such as NSI, PCL-5 and PHQ-8 may provide a more comprehensive understanding of symptom improvement and realistic view of expectations for what would be deemed recovery to pre-injury symptom levels.

Concussion significantly impacts cognitive, physical and mental health, and active duty service members (SMs) are at high risk due to their occupation demands.The Patient Global Impression of Change (PGIC) assesses symptom improvement, as perceived by the patient, which may align better with usual/pre-injury level symptoms prior to injury compared to other common measures of neurobehavioral and mental health symptoms for concussion patients.A comprehensive approach in which PGIC is included in symptom assessment may provide a better understanding of symptom improvement and provide a more realistic view of expectations for what would be deemed recovery to usual/pre-injury level or improvement in symptoms.

Self-reported mild TBI and postconcussive symptoms in a peacetime active duty military population: effect of multiple TBI history versus single mild TBI.

OBJECTIVE: To investigate the potential cumulative impact of mild traumatic brain injury (MTBI) on postconcussive symptoms. PARTICIPANTS: A total of 224 active duty soldiers reporting MTBI within 1 year of testing. For 101, this MTBI was their only reported traumatic brain injury (TBI); 123 had sustained at least 1 additional MTBI during their lifetime. A No TBI control group (n = 224) was included for comparison. MAIN MEASURE: Self-report symptoms data via questionnaire. Within time since injury subgroups (≤3 months; Post-3 months), symptom endorsement (no symptoms, 1 or 2 symptoms, 3+ symptoms) among soldiers with 1 MTBI was compared with that of soldiers with 2 or more MTBIs. Injured soldiers' symptom endorsement was compared with that of soldiers who had not sustained a TBI. RESULTS: Among the recently injured (≤3 months), those with 2 or more MTBIs endorsed significantly more symptoms than those with 1 MTBI: 67% of soldiers with 2 or more MTBIs reported 3+ symptoms, versus 29% of One MTBI soldiers. Among Post-3 month soldiers, there were no significant differences between MTBI groups. Overall, soldiers with MTBI endorsed significantly more symptoms than those without TBI. CONCLUSION: Past experience of MTBI may be a risk factor for increased symptom difficulty for several months postinjury. Clinicians should ascertain lifetime history of brain injury when evaluating patients for MTBI.

Influence of bodily injuries on symptom reporting following uncomplicated mild traumatic brain injury in US military service members.

OBJECTIVE: : To examine the relations among bodily injuries, traumatic stress, and postconcussion symptoms in a sample of combat-injured US service members who sustained a mild traumatic brain injury. PARTICIPANTS: : One hundred and thirty-seven service members evaluated and treated at Walter Reed Army Medical Center following medical evacuation from the combat theater of Operation Enduring Freedom and Operation Iraqi Freedom. All had sustained an uncomplicated mild traumatic brain injury and concurrent bodily injuries. PROCEDURE: : Participants completed 2 symptom checklists within 3 months of injury. Severity of bodily injuries was quantified with a modified version of the Injury Severity Score that excluded intracranial injuries (ISSmod). Participants were classified into 4 ISSmod groups: minor (n = 17), moderate (n = 48), serious (n = 40), severe/critical (n = 32). MAIN OUTCOME MEASURES: : Neurobehavioral Symptom Inventory (NBSI) and the Posttraumatic Stress Disorder Checklist-Civilian version (PCLC). RESULTS: : There was a significant negative association between ISSmod scores and the NBSI and PCLC total scores. There were significant main effects across the 4 groups for the NBSI and PCLC total scores. The highest NBSI and PCLC scores were consistently found in the ISSmod minor group, followed by the moderate, serious, and severe/critical groups. CONCLUSIONS: : While it might be expected that greater comorbid physical injuries would be associated with greater symptom burden, in this study as the severity of bodily injuries increased, symptom burden decreased. Hypothesized explanations include: underreporting of symptoms; increased peer support; disruption of fear conditioning due to acute morphine use; or delayed expression of symptoms.

An Initial Psychometric Analysis of the Brain Gauge Tactile-Based Test Battery and Its Potential for Clinical Use Assessing Patients With Acute Mild Traumatic Brain Injury.

OBJECTIVE: A new brief computerized test battery that uses tactile stimulation, Brain Gauge (BG), has been proposed as a cognitive assessment aid and its developers have reported an almost perfect ability to distinguish acute mild traumatic brain injury (mTBI) patients from healthy controls. This investigation attempted to replicate those results and serve as an initial psychometrically and clinically focused analysis of BG. METHODS: BG scores from 73 military service members (SM) assessed within 7 days after having a clinically diagnosed mTBI were compared to 100 healthy SMs. Mean scores were compared, score distributions were examined, and univariate and multivariate base rate analyses of low scores were performed. RESULTS: SMs with mTBI had statistically significantly worse performance on both BG Reaction Time (RT) tests and the Sequential Amplitude Discrimination test as reflected by higher mean RT and RT variability and higher minimum detectable amplitude difference. SMs with mTBI also had a significantly lower whole-battery composite (i.e., Cortical Metric Symptom Score). Larger proportions of SMs with mTBI had lower overall performance than controls. However, at most only 26.9% of those with mTBI performed at potentially clinically meaningful cutoffs that were defined as various numbers of low scores that were prevalent in no more than 10% of the control group, which is equivalent to specificity ≥90% and sensitivity ≤26.9% for mTBI. CONCLUSION: Our analysis did not replicate the high level of classification accuracy reported by BG's developers. Pending further psychometric development, BG may have limited clinical utility for assessing mTBI patients.

Presenting symptoms as prognostic measures of mental health recovery among service members with concussion.

Background: Comorbid mental illness may negatively impact recovery from concussion. This study evaluated whether the level of symptom clusters at clinic intake contribute to poor mental health recovery in concussed patients during treatment, which may in turn serve as a target intervention. Objective: The objective of this study is to examine the association between the level of initial symptoms and mental health symptoms among service members with concussion. Methods: Data were obtained from 483 active duty service members treated in interdisciplinary treatment programs for traumatic brain injury, all of which were concussions. Pre-treatment symptom clusters included self-reported hyperarousal, dissociation/depression, cognitive dysfunction/headache and neurological symptoms. The outcomes, clinically-relevant decreases in depressive symptoms (assessed by the 8-item Patient Health Questionnaire, PHQ-8) and PTSD symptoms (assessed by the PTSD Checklist for DSM-5, PCL-5), were defined as a decrease in PHQ-8 > 5 and PCL-5 > 7, respectively. Poisson regression with robust error variance was used to evaluate the relationship between the level of each symptom cluster and clinically-relevant decrease in outcomes. Results: Participants with higher (vs. lower) levels of pre-treatment hyperarousal and dissociation/depression symptom cluster were less likely to improve in depressive and PTSD symptoms during treatment. The level of cognitive/headache and neurological symptom clusters were not significantly associated with any symptom changes. Conclusion: These findings support the need for individualized treatment for symptoms identified and treated after determining concussion history, with particular attention to high levels of hyperarousal and dissociation/depression prior to treatment.

Military TBI-What civilian primary care providers should know.

In June 2019, the Department of Veterans Affairs (VA) launched the VA Mission Act, which expanded veterans' health-care access to the private sector. Since civilian primary care providers may see more veterans in their practice, it will be important to understand the unique experiences, comorbidities, and culture of this population in order to provide optimal care. Military service members (SMs) are at an increased risk for traumatic brain injury (TBI), and comorbidities, such as post traumatic stress disorder (PTSD), increasing the likelihood of prolonged symptoms. Military training and repetitive low-level blast exposure may cause symptoms similar to TBI or increase long-term negative effects in SMs. Military culture often has a strong influence in this population. Those who serve in the military identify with military values and have a strong team mentality, which places emphasis on the mission above all else, not accepting defeat, and not ever leaving a fellow SM behind. These values can impact the way a SM/veteran seeks care and/or communicates with his or her health-care provider. Taking a detailed history to understand how these factors apply, as well as screening for mental health comorbidities, are recommended. Understanding the military cultural influences can assist in promoting a stronger therapeutic alliance and encourage more open communication. Ultimately, it is the trusting and respectful relationship between the SM/veteran and the provider that will determine the most effective treatment and result in the most effective resolution of TBI and comorbid symptoms.

Traumatic brain injury, posttraumatic stress disorder, and postconcussive symptom reporting among troops returning from iraq.

OBJECTIVES: Analyze the contribution of mild traumatic brain injury (mTBI) and/or posttraumatic stress disorder (PTSD) to the endorsement of postconcussive (PC) symptoms during Post Deployment Health Assessment. Determine whether a combination of mTBI and PTSD was more strongly associated with symptoms than either condition alone. METHODS: Cross-sectional study design where both the exposure, mTBI and/or PTSD, and the outcomes of interest, PC symptoms, were ascertained after return from deployment. Subjects were injured soldiers (n = 1247) from one Fort Carson Brigade Combat Team (n = 3973). MAIN OUTCOME MEASURES: Positive history of PC symptoms. RESULTS: PTSD and mTBI together were more strongly associated with having PC symptoms (adjusted prevalence ratio 6.27; 95% CI: 4.13-9.43) than either mTBI alone (adjusted prevalence ratio = 4.03; 95% CI: 2.67-6.07) or PTSD alone (adjusted prevalence ratio = 2.74; 95% CI: 1.58-4.74) after adjusting for age, gender, education, rank, and Military Occupational Specialty. CONCLUSIONS: In soldiers with histories of physical injury, mTBI and PTSD were independently associated with PC symptom reporting. Those with both conditions were at greater risk for PC symptoms than those with either PTSD, mTBI, or neither. Findings support the importance of continued screening for both conditions with the aim of early identification and intervention.

An Investigation of the Accuracy of Reaction Time Measurements on ANAM4 TBI-MIL Across Three Computer Platforms.

STUDY DESIGN: Using two observational methods and a within-subjects, counterbalanced design, this study aimed to determine if a computer's hardware and software settings significantly affected reaction time (RT) on the Automated Neuropsychological Assessment Metrics (Version 4) Traumatic Brain Injury Military (ANAM4 TBI-MIL). METHODS: Three computer platforms were investigated: Platform 1-older computers recommended for ANAM4 TBI-MIL administration, Platform 2-newer computers with settings downgraded to run like the older computers, and Platform 3-newer computers with default settings. Two observational methods were used to compare measured RT to observed RT on all three platforms: 1, a high-speed video analysis to compare the timing of stimulus onset and response to the measured RT and 2, comparing a preset RT delivered by a robotic key actuator activated by optic detector to the measured RT. Additionally, healthy active duty service members (n = 169) were administered a brief version of the ANAM4 TBI-MIL battery on each of the three platforms. RESULTS: RT differences were observed with both the high-speed video and robotic arm analyses across all three computer platforms, with the smallest discrepancies between observed and measured RT on Platform 1, followed by Platform 2, then Platform 3. When simple reaction time (SRT) raw and standardized scores obtained from the participants were compared across platforms, statistically significant and clinically meaningful differences were seen, especially between Platforms 1 and 3. CONCLUSIONS: A computer's configurations have a meaningful impact on ANAM SRT scores. The difference in an individual's performance across platforms could be misinterpreted as clinically meaningful change.

Developing an Executive Functioning Composite Score for Research and Clinical Trials.

OBJECTIVE: Executive functioning encompasses interactive cognitive processes such as planning, organization, set-shifting, inhibition, self-monitoring, working memory, and initiating and sustaining motor and mental activity. Researchers therefore typically assess executive functioning with multiple tests, each yielding multiple scores. A single composite score of executive functioning, which summarizes deficits across a battery of tests, would be useful in research and clinical trials. This study examines multiple candidate composite scores of executive functioning using tests from the Delis-Kaplan Executive Function System (D-KEFS). METHOD: Participants were 875 adults between the ages of 20 and 89 years from the D-KEFS standardization sample. Seven Total Achievement scores were used from three tests (i.e., Trail Making, Verbal Fluency, and Color-Word Interference) to form eight composite scores that were compared based on their psychometric properties and association with intelligence (IQ). RESULTS: The distributions of most composite scores were mildly to severely skewed, and some had a pronounced ceiling effect. The composite scores all showed a medium positive correlation with IQ. The composite scores were highly intercorrelated in the total sample and in four IQ subgroups (i.e., IQ <89, 90-99, 100-109, 110+), with some being so highly correlated that they appear redundant. CONCLUSIONS: This study is part of a larger research program developing a cognition endpoint for research and clinical trials with sound psychometric properties and utility across discrepant test batteries. Future research is needed to examine the reliability and ecological validity of these composite scores.

Performance on the Automated Neuropsychological Assessment Metrics in a nonclinical sample of soldiers screened for mild TBI after returning from Iraq and Afghanistan: a descriptive analysis.

PURPOSE: To characterize cognitive test performance in a sample of US Army soldiers who had served in Iraq and Afghanistan and were tested after returning to their home base. To determine whether if a self-reported history of deployment-related traumatic brain injury (TBI), lifetime history of TBI, and the current postconcussive symptom status affected cognitive test performance. METHODS: A convenience sample of 956 soldiers was administered the Automated Neuropsychological Assessment Metrics (ANAM) test battery as well as questionnaires asking about deployment-related TBI, lifetime TBI history, and current TBI-related symptoms. RESULTS: Consistent with past mild TBI (MTBI) research, having a history of deployment-related MTBI up to 2 years prior to cognitive testing was not associated with poor ANAM performance after deployment. There also were no associations between poor ANAM performance and the number of lifetime TBIs, and injury severity and the number of problematic postconcussive symptoms. CONCLUSIONS: A history of self-reported MTBI or current postconcussive symptoms does not increase the risk of cognitive impairment in service members returning from Iraq and Afghanistan.