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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.

Objective The Automated Neuropsychological Assessment Metrics (Version 4) Traumatic Brain Injury Military (ANAM4 TBI-MIL) is commonly administered among U.S. service members both pre-deployment and following TBI. The current study used the ANAM4 TBI-MIL to develop a cognition summary score for TBI research and clinical trials, comparing eight composite scores based on their distributions and sensitivity/specificity when differentiating between service members with and without mild TBI (MTBI). Method Male service members with MTBI (n = 56; Mdn = 11 days-since-injury) or no self-reported TBI history (n = 733) completed eight ANAM4 TBI-MIL tests. Their throughput scores (correct responses/minute) were used to calculate eight composite scores: the overall test battery mean (OTBM); global deficit score (GDS); neuropsychological deficit score-weighted (NDS-W); low score composite (LSC); number of scores Results The OTBM and ACS were normally distributed. Other composites had skewed, zero-inflated distributions (62.9% had GDS = 0). All composites differed significantly between participants with and without MTBI (p < .001), with deficit scores showing the largest effect sizes (d = 1.32–1.47). The Area Under the Curve (AUC) was lowest for number of scores ≤5th percentile (AUC = 0.653) and highest for the LSC, OTBM, ACS, and NDS-W (AUC = 0.709–0.713). Conclusions The ANAM4 TBI-MIL has no well-validated composite score. The current study examined multiple candidate composite scores, finding that deficit scores showed larger group differences than the OTBM, but similar AUC values. The deficit scores were highly correlated. Future studies are needed to determine whether these scores show less redundancy among participants with more severe TBIs.

Objective To assess agreement between four brief computerized neurocognitive assessment tools (CNTs), ANAM, CogState, CNS Vital Signs, and ImPACT, by comparing rates of low scores. Methods Four hundred and six US Army service members (SMs) with and without acute mild traumatic brain injury completed two randomly assigned CNTs with order of administration also randomly assigned. We performed a base rate analysis for each CNT to determine the proportions of SMs in the control and mTBI groups who had various numbers of scores that were 1.0+, 1.5+, and 2.0+ standard deviations below the normative mean. We used these results to identify a hierarchy of low score levels ranging from poorest to least poor performance. We then compared the agreement between every low score level from each CNT pair administered to the SMs. Results More SMs in the mTBI group had low scores on all CNTs than SMs in the control group. As performance worsened, the association with mTBI became stronger for all CNTs. Most if not all SMs who performed at the worst level on any given CNT also had low scores on the other CNTs they completed but not necessarily at an equally low level. Conclusion These results suggest that all of the CNTs we examined are broadly similar but still retain some psychometric differences that need to be better understood. Furthermore, the base rates of low scores we present could themselves be useful to clinicians and researchers as a guide for interpreting results from the CNTs.

Objective Research has demonstrated reaction time variability (RTV) as a potentially sensitive metric for post-concussion assessments. The Brain Gauge Clinical Metrics battery (BG) device uses tactile sensory stimulation to elicit a response, increasing accuracy to Methods We administered BG to 98 healthy control service members (SMs) and 64 SMs within 7 days of a medically diagnosed concussion. The battery includes simple RT and repeated simple RT subtests with RT variability (RTV) for each test calculated as the sd of mean RT for each participant. We used t-tests and gamma regression to compare group RT and RTV means. “Cutoffs” based on percentiles of the control group RTV distribution were calculated and the proportion of each group falling below these cutoffs was determined. Results There were statistically significant differences with large effect sizes between groups across all four metrics. The proportion of participants in the concussion group falling below the cutoffs was higher than among controls, with large effect sizes. T-tests and gamma regression showed that group mean RT and RTV differed significantly under multiple distributional assumptions. Conclusions Both RT and RTV using the BG somatosensory device demonstrated the ability to discriminate between healthy control SMs and SMs with acute concussion. This is further evidence that RTV is a sensitive measure for acute concussion and the use of a tactile sensory stimulus may represent an improvement over a visual stimulus.

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.

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

Cognitive impairment is a core clinical feature of traumatic brain injury (TBI). After TBI, cognition is a key determinant of post-injury productivity, outcome, and quality of life. As a final common pathway of diverse molecular and microstructural TBI mechanisms, cognition is an ideal endpoint in clinical trials involving many candidate drugs and nonpharmacological interventions. Cognition can be reliably measured with performance-based neuropsychological tests that have greater granularity than crude rating scales, such as the Glasgow Outcome Scale-Extended, which remain the standard for clinical trials. Remarkably, however, there is no well-defined, widely accepted, and validated cognition endpoint for TBI clinical trials. A single cognition endpoint that has excellent measurement precision across a wide functional range and is sensitive to the detection of small improvements (and declines) in cognitive functioning would enhance the power and precision of TBI clinical trials and accelerate drug development research. We outline methodologies for deriving a cognition composite score and a research program for validation. Finally, we discuss regulatory issues and the limitations of a cognition endpoint.

Objective: The purpose of this study was to examine the prevalence and stability of symptom reporting in a healthy military sample and to develop reliable change indices for two commonly used self-report measures in the military health care system. Participants and method: Participants were 215 U.S. active duty service members recruited from Fort Bragg, NC as normal controls as part of a larger study. Participants completed the Neurobehavioral Symptom Inventory (NSI) and Posttraumatic Checklist (PCL) twice, separated by approximately 30 days. Results: Depending on the endorsement level used (i.e. ratings of ‘mild’ or greater vs. ratings of ‘moderate’ or greater), approximately 2–15% of this sample met DSM-IV symptom criteria for Postconcussional Disorder across time points, while 1–6% met DSM-IV symptom criteria for Posttraumatic Stress Disorder. Effect sizes for change from Time 1 to Time 2 on individual symptoms were small (Cohen’s d = .01 to .13). The test–retest reliability for the NSI total s...

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.

Objective CogState is a brief computerized test battery used to assess cognitive function. We compare intra-individual agreement between CogState and a battery of traditional neuropsychological tests using rates of low scores. Methods Complete and valid data from 246 healthy soldiers and 177 soldiers ≤ 7 days from sustaining mild TBI (mTBI) were used in this analysis. All soldiers were consecutively administered CogState and a traditional test battery consisting of: TOPF, WAIS-IV, CVLT-II, RCFT, DKEFS, and CPT-II. We performed base rate analyses of both batteries to determine the proportions of soldiers who had various numbers of scores that were 1.0+, 1.5+, and 2.0+ standard deviations below the normative mean. We used those rates to place Soldiers into a “low score hierarchy” ranging from the least poor (i.e. ~ > 10th %ile) to the worst overall performance (i.e. ~ ≤ 10th %ile). We then compared agreement between the batteries at each of those levels. Results More soldiers with mTBI had low scores than healthy soldiers on both batteries. Of the soldiers who performed at the worst level on one battery, 95.1% from CogState and 70.6% from traditional had some level of poor performance on the other battery. However, of the soldiers who performed at the worst level on either battery, only 31.7% from CogState and 38.2% from traditional also performed at the worst level on the other battery. Conclusion These batteries similarly identify poor performance to a degree, though with some potentially meaningful differences still present.

Objective Several cognition composite scores have been developed for potential use in traumatic brain injury clinical trials. This analysis examined the equivalence of overall test battery mean (OTBM) from two different test batteries administered consecutively to the same subjects. Methods Soldiers were administered the Automated Neuropsychological Assessment Metrics (version 4) TBI-MIL (ANAM4) computerized battery and D-KEFS as part of a larger study comparing within-subject performance from different neuropsychological test batteries. Data from 121 soldiers with complete and valid data on both ANAM4 and D-KEFS and no recent TBI were used in this analysis. OTBMs were calculated for ANAM4 and the seven D-KEFS achievement scores. The OTBMs from the 121 soldiers were ranked from lowest to highest and the percentile rankings from each battery were compared. For each soldier, the differences between the percentile ranks from each battery were also calculated. Results Only 53.8% of soldiers who scored below the 20th percentile on ANAM4 also scored below the 20th percentile on D-KEFS. Furthermore, only 47.8% of soldiers who scored at or above the 80th percentile on ANAM4 also scored in that range on D-KEFS. Some soldiers’ performance on each battery diverged by large amounts, for example from 59.5 to 82.6 percentage points. Correlation analysis revealed that the OTBMs and percentile rankings from both batteries were modestly correlated (OTBM r = 0.515, p Conclusion These results suggest that comparing similar cognition composites from different neuropsychological test batteries from different studies in a meta-analytic manner may not be feasible due to psychometric difference between batteries.

Objective In statistics, larger sample studies are assumed to more accurately reflect the population mean and thus assumed to have less random error. We use an overall test battery mean (OTMB) from the D-KEFS taken from two different studies to evaluate two methods of weighting means when aggregating data: Method 1, assuming that larger studies have less error and thus giving their variances more weight and Method 2, assuming equal error and uncertainty across studies and assigning equal weight to variances from all studies. Methods The OTBM from seven D-KEFS achievement scores was calculated from a D-KEFS normative sample (n = 854), and aggregated with the same D-KEFS OTBM from a healthy military sample (n = 246). Weighted averages were calculated for selected points from the distributions of scores (e.g., mean, median, etc.). Variances, standard errors, and 95% confidence intervals for the weighted means were calculated using Method 1 and Method 2, as described above. Results The weighted mean OTBM from both samples was 51.48. The variance, standard error, and confidence interval using Method 1 were 11.63, 2.41, and 46.76–56.21, respectively, and using Method 2 were 16.74, 4.09, and 43.6–59.50, respectively. Conclusion Method 1 results in weighted means with less variability, though may result in larger studies disproportionately reducing measurement error. Method 2 results in greater variances, standard errors, and wider confidence intervals and somewhat mutes the impact of larger studies. Researchers should consider the implications for their results when choosing a method for assessing the precision of their weighted means.

Objective Computerized cognitive tests are vulnerable to measurement error due to hardware and software configurations of the administration computer. Though automatic score corrections are often provided to account for this, they may mask subtle individual variations in test performance. We investigated the group and individual impact of correcting for measurement error while accounting for possible order effects using data from a larger study of computer platform effects on reaction time measurement. Methods ANAM4 TBI Military’s Simple Reaction Time (SRT) subtest was administered repeatedly on three different computer platforms. We compare two of those platforms: Platform 1, a Dell D630 configured for ANAM4 TBI Military administration; Platform 3, a Dell E6540 with default settings. A mechanical arm with a preset RT was first used to capture measurement error on each platform. SRT was then administered to healthy US Army soldiers in a randomly selected administration order, such that platform 1 was first and platform 3 was third for n = 58 and platform 3 was first and platform 1 second for n = 53. Results Platform 3 was on average 43.06 ms slower than Platform 1. Group analyses suggested applying a 43.06 ms correction to Platform 3 scores resulted in scores similar to Platform 1. However, it appears there were subtle practice and fatigue effects for some individuals that were possibly masked by the score correction. Conclusion Correcting for error due to computer configurations is important in RT measurement, though there may be subtle individual statistical and clinical implications that are lost at a group analysis level.

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 (

Base rates of low ANAM4 TBI-MIL scores were calculated in a convenience sample of 733 healthy male active duty soldiers using available military reference values for the following cutoffs: ≤2nd percentile (2 SDs), ≤5th percentile

Objective The Automated Neurological Assessment Metrics (Version 4) Traumatic Brain Injury Military (ANAM4 TBI-MIL) battery is widely used by the US military to assess cognitive function. We compare intra-individual agreement between ANAM4 TBI-MIL and a battery of traditional neuropsychological tests using rates of low scores. Methods Complete and valid data from 246 healthy soldiers and 177 soldiers ≤7 days from sustaining mild TBI (mTBI) were used in this analysis. All soldiers were consecutively administered ANAM4 TBI-MIL and a traditional test battery consisting of: TOPF, WAIS-IV, CVLT-II, RCFT, DKEFS, and CPT-II. We performed base rate analyses of both batteries to determine the proportions of soldiers who had various numbers of scores that were 1.0+, 1.5+, and 2.0+ standard deviations below the normative mean. We used those rates to place Soldiers into a “low score hierarchy” ranging from the least poor (i.e. ~≥10th %ile) to the worst overall performance (i.e. ~≤10th %ile). We then compared agreement between the batteries at each of those levels. Results More soldiers with mTBI had low scores than healthy soldiers on both batteries. Of the soldiers who performed at the worst level on one battery, 88.1% from ANAM and 100% from traditional had some level of poor performance on the other battery. However, of the soldiers who performed at the worst level on either battery, only 58.3% from ANAM and 50.0% from traditional also performed at the worst level on the other battery. Conclusion These batteries similarly identify poor performance to a degree, though with some potentially meaningful differences still present.

Objective It is not uncommon for healthy individuals to have one or more low scores on a battery of cognitive tests. The number of scores produced by the battery by itself can affect the probability of having low scores. The purpose of this study is to examine the rates of low scores on a battery of commonly used neuropsychological tests in soldiers with and without acute mTBI. Methods Data from 246 healthy soldiers and 177 soldiers evaluated within seven days of sustaining a mTBI and who had complete and valid data were used in this analysis. All soldiers completed the TOPF, WAIS-IV, CVLT-II, RCFT, DKEFS, and CPT-II. The CARB was used as a measure of effort. For each group, we determined the proportions of soldiers who had various numbers of scores that were 1.0 or more, 1.5 or more, 2.0 or more standard deviations below the normative means for each score. We used prevalence ratios to compare the proportions with low scores in each group. Results Low scores were common in both groups (93.1% and 96.0% of controls and mTBI cases, respectively, had at least one score 1.0+ SDs below norm, 57.7% and 79.1% had at least one score 1.5+ SDs below norm, while 30.5% and 48.0% had at least score 2.0+ SDs below norm). Low scores were more common in the mTBI group. Conclusion Examining rates of low scores can help identify clinically meaningful performance decrements across an entire battery when large numbers of scores are available.

Computerized neurocognitive assessment tools (NCATs) are increasingly used for baseline and post-concussion assessments. To date, NCATs have not demonstrated strong test-retest reliabilities. Most studies have used non-military populations and different methodologies, complicating the determination of the utility of NCATs in military populations. The test-retest reliability of four NCATs (Automated Neuropsychological Assessment Metrics 4 [ANAM4], CNS-Vital Signs, CogState, and Immediate Post-Concussion Assessment and Cognitive Test [ImPACT]) was investigated in a healthy active duty military sample. Four hundred and nineteen Service Members were randomly assigned to take one NCAT and 215 returned after approximately 30 days for retest. Participants deemed to have inadequate effort during one or both testing sessions, according to the NCATs scoring algorithms, were removed from analyses. Each NCAT had at least one reliability score (intraclass correlation) in the "adequate" range (.70-.79), only ImPACT had one score considered "high" (.80-.89), and no scores met "very high" criteria (.90-.99). However, overall test-retest reliabilities in four NCATs in a military sample are consistent with reliabilities reported in the literature and are lower than desired for clinical decision-making.

Objective Computerized neurocognitive assessment tools (NCATS) are often used as a screening tool to identify cognitive deficits after mild traumatic brain injury (mTBI). However, differing methodology across studies renders it difficult to identify a consensus regarding the validity of NCATs. Thus, studies where multiple NCATs are administered in the same sample using the same methodology are warranted. Method We investigated the validity of four NCATs: the ANAM4, CNS-VS, CogState, and ImPACT. Two NCATs were randomly assigned and a battery of traditional neuropsychological (NP) tests administered to healthy control active duty service members (n = 272) and to service members within 7 days of an mTBI (n = 231). Analyses included correlations between NCAT and the NP test scores to investigate convergent and discriminant validity, and regression analyses to identify the unique variance in NCAT and NP scores attributed to group status. Effect sizes (Cohen's f2) were calculated to guide interpretation of data. Results Only 37 (0.6%) of the 5,655 correlations calculated between NCATs and NP tests are large (i.e. r ≥ 0.50). The majority of correlations are small (i.e. 0.30 > r ≥ 0.10), with no clear patterns suggestive of convergent or discriminant validity between the NCATs and NP tests. Though there are statistically significant group differences across most NCAT and NP test scores, the unique variance accounted for by group status is minimal (i.e. semipartial R2 ≤ 0.033, 0.024, 0.062, and 0.011 for ANAM4, CNS-VS, CogState, and ImPACT, respectively), with effect sizes indicating small to no meaningful effect. Conclusion Though the results are not overly promising for the validity of the four NCATs we investigated, traditional methods of investigating psychometric properties may not be appropriate for computerized tests. We offer several conceptual and methodological considerations for future studies regarding the validity of NCATs.

Computerized neurocognitive assessment tools (NCATs) have become a common way to assess postconcussion symptoms. As there is increasing research directly comparing multiple NCATs to each other, it is important to consider the impact that order of test administration may have on the integrity of the results. This study investigates the impact of administration order in a study of four different NCATs; Automated Neuropsychological Assessment Metrics (ANAM4), CNS Vital Signs (CNS-VS), CogState, and Immediate Post-Concussion Assessment and Cognitive Test (ImPACT). A total of 272 healthy active duty Service Members were enrolled into this study. All participants were randomly assigned to take two of the four NCATs with order of administration counterbalanced. Analyses attempted to investigate the effect of administration order alone (e.g., Time 1 versus Time 2), the effect of administration order combined with the impact of the specific NCAT received at Time 1, and only the impact of the Time 1 NCAT on Time 2 score variability. Specifically, independent samples t tests were used to compare Time 1 and Time 2 scores within each NCAT. Additional t tests compared Time 1 to Time 2 scores with Time 2 scores grouped by the NCAT received at Time 1. One-way analysis of variance (ANOVA) was used to compare only an NCAT's Time 2 scores grouped by the NCAT received at Time 1. Cohen's d effect sizes were calculated for all comparisons. The results from this study revealed statistically significant order effects for CogState and CNS-VS, though with effect sizes generally indicating minimum practical value, and marginal or absent order effects for ANAM4 and ImPACT with no clinically meaningful implications. Despite finding minimal order effects, clinicians should be mindful of the impact of administering multiple NCATs in a single session. Future studies should continue to be designed to minimize the potential effect of test administration order.

The purpose of this study was to examine the prevalence and stability of symptom reporting in a healthy military sample and to develop reliable change indices for two commonly used self-report measures in the military health care system.Participants were 215 U.S. active duty service members recruited from Fort Bragg, NC as normal controls as part of a larger study. Participants completed the Neurobehavioral Symptom Inventory (NSI) and Posttraumatic Checklist (PCL) twice, separated by approximately 30 days.Depending on the endorsement level used (i.e. ratings of 'mild' or greater vs. ratings of 'moderate' or greater), approximately 2-15% of this sample met DSM-IV symptom criteria for Postconcussional Disorder across time points, while 1-6% met DSM-IV symptom criteria for Posttraumatic Stress Disorder. Effect sizes for change from Time 1 to Time 2 on individual symptoms were small (Cohen's d = .01 to .13). The test-retest reliability for the NSI total score was r = .78 and the PCL score was r = .70. An eight-point change in symptom reporting represented reliable change on the NSI total score, with a seven-point change needed on the PCL.Postconcussion-like symptoms are not unique to mild TBI and are commonly reported in a healthy soldier sample. It is important for clinicians to use normative data when evaluating a service member or veteran and when evaluating the likelihood that a change in symptom reporting is reliable and clinically meaningful.

OBJECTIVE:: To examine the relations among bodily injuries, traumatic stress, and post-concussion 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: under-reporting of symptoms; increased peer support; disruption of fear conditioning due to acute morphine use; or delayed expression of symptoms. Language: en

Objective: To evaluate alternative models of symptom clusters for the 22-item Neurobehavioral Symptom Inventory. Participants: Three military samples, including 2 nonclinical samples (n = 2420, n = 4244) and 1 sample of individuals with recent head injury (n = 617). Methods: In the first sample, exploratory factor analysis of Neurobehavioral Symptom Inventory responses was performed with tests of significant factors and model fit. In the other 2 samples, confirmatory factor analysis evaluated the fit of 3 models: 2- and 3-factor models based on the initial exploratory factor analysis, and a 9-factor model based on prior research. Main Outcome Measures: The exploratory factor analysis used 2 tests for the number of factors: Parallel Analysis and Minimum Average Partial test. Confirmatory factor analysis models were evaluated using 2 measures of model fit, Root Mean Square Error of Approximation and Comparative Fit Index. Results: Postconcussive symptoms can be described accurately by the 9 factors. However, the model of 3 intercorrelated factors, reflecting cognitive, affective, and somatic/sensory symptoms, fits the data more parsimoniously with little loss in model fit. Conclusion: Although the 9-cluster result from prior research provides a valid description of the relations among items of the inventory, a 3-factor model, consisting of somatic/sensory, affective, and cognitive factors, provides nearly as good a fit to the data, with greater parsimony. We encourage clinicians and researchers to conceptualize the Neurobehavioral Symptom Inventory in terms of 3 coherent clusters of symptoms rather than as 22 individual items.

The current study examined the performance of active duty soldiers on the Automated Neuropsychological Assessment Metrics (ANAM) traumatic brain injury test battery, to expand the reference data for use in military settings. The effects of age and gender on cognitive performance also were explored. The ANAM traumatic brain injury battery, consisting of six performance tests and two subjective scales, was administered to a sample of healthy active duty soldiers (N = 5,247) as part of a concussion surveillance program. Performance means and SDs, stratified according to age and gender, are reported as reference data. In addition, the impact of age and gender on performance measures was analyzed. Because ANAM is rapidly being adopted for use in many military medical and research applications, the establishment of these reference values is invaluable, particularly for assisting with rapid accurate evaluation and treatment in clinical settings.

Computerized cognitive testing with software programs such as the Automated Neuropsychological Assessment Metrics (ANAM) have long been used to assess cognition in military samples. This study desc...

OBJECTIVE: Preliminary assessment of a new instrument, the Brief Traumatic Brain Injury Screen (BTBIS). DESIGN: Cross-sectional study of 596 soldiers returning from Iraq and/or Afghanistan, comparing the consistency of their reports of traumatic brain injury (TBI) across instruments with similar TBI questions, and in a brief follow-up interview. SETTING: Military base. MEASURES: Self-reported probable TBI on the BTBIS and on 2 longer questionnaires, and a brief follow-up interview. RESULTS: Self-reports of probable TBI were higher on the BTBIS, than on the longer instruments. Participants who screened positive on the BTBIS generally provided consistent information about probable TBI in the follow-up interview. CONCLUSIONS: In this initial study, the BTBIS demonstrated promise as part of a triage process in mass casualty situations, permitting individuals with probable TBI to self-report injury and continued symptoms. Further study, including full validation and reliability assessment, is warranted and required before these screening tools can be fully evaluated. Language: en

Many factors are considered during ballistic helmet design, including comfort, weight, fit, and maintainability. These factors affect soldiers' decisions about helmet use; therefore, rigorous research about soldiers' real-life experiences with helmets is critical to assessing a helmet's overall protective efficacy. This study compared soldiers' satisfaction and problem experience with the advanced combat helmet (ACH) and the personal armor system for ground troops (PASGT) helmet. Data were obtained from surveys of soldiers at Fort Bragg, North Carolina. Ninety percent of ACH users were satisfied overall with their helmet, but only 9.5% of PASGT users were satisfied (p < 0.001). The most frequently reported problems for the ACH involved malfunctioning helmet parts. The most frequently reported problems for the PASGT involved discomfort. This analysis indicated that there was a strong soldier preference for the ACH over the PASGT, which could enhance its already superior protective qualities. It also demonstrated the usefulness of soldiers' assessments of protective equipment.

The Automated Neuropsychological Assessment Metrics (ANAM) is a computerized measure of processing speed, cognitive efficiency, and memory. This study describes performance and psychometric properties of ANAM in an active duty, healthy military sample (N = 2,371) composed primarily of young (18–46 years) adult males. Rarely have neuropsychological reference values for use with individuals in the military been derived from a large, active duty military population, and this is the first computerized neuropsychological test battery with military-specific reference values. Although these results do not provide demographically corrected, formal normative data, they provide reference points for neuropsychologists and other health care providers who are using ANAM data in research or clinical settings, with patients of comparable demographics to the present sample.

Traumatic brain injuries (TBI) sustained in combat frequently co-occur with significant bodily injuries. Intuitively, more extensive bodily injuries might be associated with increased symptom reporting. In 2012, however, French et al. demonstrated an inverse relation between bodily injury severity and symptom reporting. This study expands on that work by examining the influence of location and severity of bodily injuries on symptom reporting after mild TBI. Participants were 579 US military service members who sustained an uncomplicated mild TBI with concurrent bodily injuries and who were evaluated at two military medical centers. Bodily injury severity was quantified using a modified Injury Severity Score (ISSmod). Participants completed the Neurobehavioral Symptom Inventory (NSI) and the Posttraumatic Stress Disorder Checklist (PCL-C), on average, 2.5 months post-injury. There was a significant negative association between ISSmod scores and NSI (r=-0.267, p0.001) and PCL-C (r=-0.273, p0.001) total scores. Using linear regression to examine the relation between symptom reporting and injury severity across the six ISS body regions, three body regions were significant predictors of the NSI total score (face; p0.001; abdomen; p=0.003; extremities; p0.001) and accounted for 9.3% of the variance (p0.001). For the PCL-C, two body regions were significant predictors of the PCL-C total score (face; p0.001; extremities; p0.001) and accounted for 10.5% of the variance. There was an inverse relation between bodily injury severity and symptom reporting in this sample. Hypothesized explanations include underreporting of symptoms, increased peer support, disruption of fear conditioning because of acute morphine use, or delayed expression of symptoms.

The purpose of this study was to identify factors that are predictive of, or associated with, high endorsement of postconcussion and posttraumatic stress symptoms following military-related traumatic brain injury (TBI). Participants were 1,600 U.S. service members (age: M = 27.1, SD = 7.1; 95.4% male) who had sustained a mild-to-moderate TBI and who had been evaluated by the Defense and Veterans Brain Injury Center at one of six military medical centers. Twenty-two factors were examined that included demographic, injury circumstances/severity, treatment/evaluation, and psychological/physical variables. Four factors were statistically and meaningfully associated with clinically elevated postconcussion symptoms: (i) low bodily injury severity, (ii) posttraumatic stress, (iii) depression, and (iv) military operation where wounded (p < .001, 43.2% variance). The combination of depression and posttraumatic stress symptoms accounted for the vast majority of unique variance (41.5%) and were strongly associated with, and predictive of, clinically elevated postconcussion symptoms [range: odds ratios (OR) = 4.24-7.75; relative risk (RR) = 2.28-2.51]. Five factors were statistically and meaningfully associated with clinically elevated posttraumatic stress symptoms: (i) low bodily injury severity, (ii) depression, (iii) a longer time from injury to evaluation, (iv) military operation where wounded, and (v) current auditory deficits (p < .001; 65.6% variance accounted for). Depression alone accounted for the vast majority of unique variance (60.0%) and was strongly associated with, and predictive of, clinically elevated posttraumatic stress symptoms (OR = 38.78; RR = 4.63). There was a very clear, strong, and clinically meaningful association between depression, posttraumatic stress, and postconcussion symptoms in this sample. Brain injury severity, however, was not associated with symptom reporting following TBI.

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. Language: en

The purpose of this study was to identify factors that are predictive of, or associated with, postconcussion symptom reporting after traumatic brain injury (TBI) in the U.S. military. Participants were 125 U.S. military service members (age: M=29.6 years, standard deviation [SD]=8.9, range=18-56 years) who sustained a TBI, divided into two groups based on symptom criteria for postconcussional disorder (PCD): PCD-Present (n=65) and PCD-Absent (n=60). Participants completed a neuropsychological evaluation at Walter Reed Army Medical Center (M=9.4 months after injury, SD=9.9; range: 1.1 to 44.8). Factors examined included demographic characteristics, injury-related variables, psychological testing, and effort testing. There were no significant group differences for age, sex, education, race, estimated premorbid intelligence, number of deployments, combat versus non-combat related injury, or mechanism of injury (p0.098 for all). There were significant main effects for severity of body injury, duration of loss of consciousness, duration of post-traumatic amnesia, intracranial abnormality, time tested post-injury, possible symptom exaggeration, poor effort, depression, and traumatic stress (p0.044 for all). PCD symptom reporting was most strongly associated with possible symptom exaggeration, poor effort, depression, and traumatic stress. PCD rarely occurred in the absence of depression, traumatic stress, possible symptom exaggeration, or poor effort (n=7, 5.6%). Many factors unrelated to brain injury were influential in self-reported postconcussion symptoms in this sample. Clinicians cannot assume uncritically that endorsement of items on a postconcussion symptom checklist is indicative of residual effects from a brain injury.

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. Language: en

to determine the potential impacts of Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF) on the incidence of TBI-related hospitalization in the active duty US Army.All active duty Army personnel hospitalized with a TBI diagnosis during fiscal years 2000 through 2006 were identified in an administrative database. Annual crude incidence rates were calculated. Two-year adjusted incidence rates were calculated to compare TBI-related hospitalization rates in the Army to rates in the age-comparable segment of the US civilian population.The overall incidence of TBI-related hospitalization in the active duty Army increased 105% from FY2000 to FY2006. There was a 60-fold increase in the hospitalization rate for TBIs attributed to weapons. The increases in TBI hospitalizations coincided with the occurrence of OEF/OIF. During OEF/OIF, the Army's hospitalization rates for moderate and severe TBIs were lower than civilian rates; however, the Army's hospitalization rate for mild TBIs was higher than civilian rates.OEF/OIF appear to have had a substantial impact on TBI-related hospitalization rates in the active duty US Army but differences between Army and civilian rates were not as excessive as expected.

This exploratory study was conducted to increase understanding of neuropsychological test performance in those with blast-related mild traumatic brain injury (mTBI). The two variables of interest for their impact on test performance were presence of mTBI symptoms and history of posttraumatic stress disorder (PTSD). Forty-five soldiers postblast mTBI, 27 with enduring mTBI symptoms and 18 without, completed a series of neuropsychological tests. Seventeen of the 45 met criteria for PTSD. The Paced Auditory Serial Addition Test (Frencham, Fox, & Mayberry, 2005; Spreen & Strauss, 1998) was the primary outcome measure. Two-sided, 2-sample t tests were used to compare scores between groups of interest. Presence of mTBI symptoms did not impact test performance. In addition, no significant differences between soldiers with and without PTSD were identified. Standard neuropsychological assessment may not increase understanding about impairment associated with mTBI symptoms. Further research in this area is indicated.

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, PCsymptoms, 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. Language: en

A basic description of severity and frequency is needed for planning healthcare delivery for any disease process. In the case of traumatic brain injury, severity is typically categorized into mild, moderate, and severe with information from a combination of clinical observation and self-report methodologies. Recent US civilian epidemiological findings measuring the frequency of mortality and morbidity of traumatic brain injury are presented, including demographic and etiological breakdowns of the data. Falls, motor vehicle accidents, and being struck by objects are the major etiologies of traumatic brain injury. US civilian and Army hospitalization trends are discussed and compared. Features of traumatic brain injuries from Operation Iraqi Freedom and Operation Enduring Freedom are discussed. Mt Sinai J Med 76:105–110, 2009.  2009 Mount Sinai School of Medicine

Objectives The objective of this article is to report the proportion of soldiers in a Brigade Combat Team (BCT) with at least 1 clinician-confirmed deployment-acquired traumatic brain injury (TBI) and to describe the nature of sequelae associated with such injuries. Participants Members of an Army unit (n = 3973) that served in Iraq were screened for history of TBI. Those reporting an injury (n = 1292) were further evaluated regarding sequelae. Of the injuries suffered, 907 were TBIs and 385 were other types of injury. The majority of TBIs sustained were mild. Methods Postdeployment, responses to the Warrior Administered Retrospective Casualty Assessment Tool (WARCAT) facilitated clinical interviews regarding injury history and associated somatic (ie, headache, dizziness, balance) and neuropsychiatric symptoms (ie, irritability, memory). Traumatic brain injury diagnosis was based on the American Congress of Rehabilitation Medicine mild TBI criteria, which requires an injury event followed by an alteration in consciousness. Results A total of 22.8% of soldiers in a BCT returning from Iraq had clinician-confirmed TBI. Those with TBI were significantly more likely to recall somatic and/or neuropsychiatric symptoms immediately postinjury and endorse symptoms at follow-up than were soldiers without a history of deployment-related TBI. A total of 33.4% of soldiers with TBI reported 3 or more symptoms immediately postinjury compared with 7.5% at postdeployment. For soldiers injured without TBI, rates of 3 or more symptoms postinjury and postdeployment were 2.9% and 2.3%, respectively. In those with TBI, headache and dizziness were most frequently reported postinjury, with irritability and memory problems persisting and presenting over time. Conclusion Following deployment to Iraq, a clinician-confirmed TBI history was identified in 22.8% of soldiers from a BCT. Those with TBI were significantly more likely to report postinjury and postdeployment somatic and/or neuropsychiatric symptoms than those without this injury history. Overall, symptom endorsement decreased over time.

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. Language: en

Military paratroopers are inherently at risk for a variety of injuries when they jump, including traumatic brain injuries (TBIs). U.S. Army paratroopers rely on their ballistic helmets for protection against TBIs when jumping. Currently, two different helmets are available to Army paratroopers, that is, the personnel armor system for ground troops helmet and the advanced combat helmet. This study compared the incidence of self-reported, jump-related TBIs in a small sample of paratroopers (N = 585) using each type of helmet. Data were obtained from surveys of soldiers at Fort Bragg, North Carolina. The overall relative risk of sustaining a TBI while jumping was 2.3 times (95% confidence interval, 1.3-4.3) higher for personnel armor system for ground troops helmet users. Most of the increase in risk was accounted for by the most-minor TBIs (American Academy of Neurology grade 1 or 2 concussion).