Automated Neuropsychological Assessment Metrics (v4) Traumatic Brain Injury Battery: military normative data.

The aim of the present study was to establish normative data for the Automated Neuropsychological Assessment Metrics (v4) Traumatic Brain Injury (ANAM4 TBI) battery in a military context. ANAM4 data from over 107,500 active duty service members ranging from 17 to 65 years of age were included in this study. The influence of the demographic variables of age and gender were also examined. These norms, stratified by age and gender, represent a more comprehensive set of norms than previously available and are provided as a representative set of norms for clinical practice. Additionally, base rates of below average performance in a normal population are provided to help inform clinical decision making.

Effects of military deployment on cognitive functioning.

Military deployment poses many risks for cognitive functioning. When deployed individuals are compared to a nondeployed control group, there is some evidence that deployment may be associated with declines in cognitive functioning. The current study examined cognitive performance before and following deployment in a large sample of active duty military personnel (N = 8002) who reported no traumatic brain injury (TBI). Cognition was assessed using the Automated Neuropsychological Assessment Metrics version 4 TBI Military (ANAM4 TBI-MIL) battery, a computer-based battery of tests measuring attention, processing speed, and general cognitive efficiency. Pre- and postdeployment scores were compared using repeated measures analyses. Although statistically significant differences were observed for all tests (with 5 of 7 tests demonstrating performance improvement), effect sizes were very small for all but 1 test, indicating that performance differences had minimal clinical significance. Likewise, determination of change for individuals using reliable change indices revealed that a very small percentage (<3%) of this presumed healthy sample showed meaningful decline in cognition following deployment. Analyses indicated that despite risks for cognitive decline while in theater, deployment had minimal to no lasting effect on cognition as measured by ANAM4 TBI-Mil upon return from deployment.

Case report: Treatment of mild traumatic brain injury with hyperbaric oxygen.

Two United States Air Force Airmen were injured in a roadside improvised explosive device (IED) blast in Iraq in January 2008. Both airmen suffered concussive injuries and developed irritability, sleep disturbances, headaches, memory difficulties and cognitive difficulties as symptoms of mild traumatic brain injury (mTBI). Six months after injury, repeat Automated Neuropsychological Assessment Metrics (ANAM) testing showed deterioration, when compared to pre-injury baseline ANAM assessment, in all measured areas (simple reaction time, procedural reaction time, code substitution learning, code substitution delayed, mathematical processing, and matching to sample). The airmen were treated with hyperbaric oxygen in treatments of 100% oxygen for one hour at 1.5 atmospheres absolute, resulting in rapid improvement of headaches and sleep disturbances, improvement in all symptoms and resolution of most symptoms. Repeat ANAM testing after completion of the hyperbaric treatments - nine months after initial injury - showed improvement in all areas, with most measures improving to pre-injury baseline levels. The airmen received no other treatment besides medical monitoring. Repeat neuropsychologic testing confirmed the improvement. We conclude that the improvement in symptoms and ANAM performance is most likely attributable to HBO treatment.

Reliability and construct validity of the Automated Neuropsychological Assessment Metrics (ANAM) mood scale.

The reliability and construct validity of the Automated Neuropsychological Assessment Metrics (ANAM) mood scale (AMS) were examined using concurrent, well-validated measures of mood and confirmatory factor analysis (CFA) with a sample of 210 volunteer college students. The AMS was given in computerized format with multiple adjectives using a visual analog Likert scale yielding seven dimensions of mood including vigor, restlessness, depression, anger, fatigue, anxiety, and happiness. All seven mood dimensions of the AMS demonstrated excellent test-retest reliability and internal consistency. Also, the AMS anxiety dimension correlated strongly with the Spielberger's State Anxiety Inventory (r=0.67) and the AMS depression dimension correlated strongly with the Beck Depression Inventory-II (r=0.71). CFA revealed that the AMS 7-factor mood model fit the data well and significantly better than an alternative, theoretically plausible model. When concurrent measures of mood were incorporated in the CFA model, the AMS demonstrated both convergent and discriminant validity. The AMS 7-factor model explained 55.12% of the total variance in the items. It was concluded that the AMS provides a brief yet reasonably complete and valid assessment of mood.

Reference data from the automated Neuropsychological Assessment Metrics for use in traumatic brain injury in an active duty military sample.

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.

Test-retest reliability and practice effects for the ANAM General Neuropsychological Screening battery.

OBJECTIVE: As the use of computer-based neurocognitive assessment is rapidly expanding, the need to systematically study and document key psychometric properties of these measures has become increasingly more salient. To meet this aim, this study examined test-retest reliability and practice effects for the Automated Neuropsychological Assessment Metrics General Neuropsychological Screening battery (ANAM GNS) in a sample of 94 community dwelling adults. METHOD: ANAM GNS was administered and then repeated (alternate form) after 30 days. Test-retest reliability, practice effects, and the standard error of measurement were calculated. Using these estimates, reliable change indices were calculated to determine degree of performance change needed to exceed chance and measurement error (with 90% confidence interval). RESULTS: The test-retest reliability for the ANAM composite score was .91. Performance significantly improved upon retest, but the effect size was small consistent with minimal practice effects. The threshold indicating change beyond chance or measurement error with 90% certainty was .9 (z-score). CONCLUSIONS: Findings suggest that the ANAM GNS has excellent test-retest reliability upon retest at 30 days. Small practice effects can be expected. Change greater than .9 standard deviations in the ANAM composite score is likely to represent meaningful clinical change. This paper presents initial psychometric data from the ANAM GNS and supports its use as a reliable measure of cognition.

Development and quality assurance of computer-based assessment batteries.

The purpose of this article is to outline critical elements in the development and quality assurance (QA) assessment of a computer-based assessment battery (CAB). The first section of the article provides an overview of the life cycle of a representative CAB, typical evolutionary stages, and many of the essential considerations for designing and developing a CAB. The second section of the article presents a model for conducting a quality assurance assessment of a CAB. A general narrative of several steps in the QA process is supported by a table of recommended QA assessment elements. Although this QA process model may not be definitive for all cases, it provides a general framework within which a systematic assessment of any CAB can be conducted.

Fundamental dimensions of subjective state in performance settings: task engagement, distress, and worry.

Subjective state constructs are defined within the traditional domains of affect, motivation, and cognition. Currently, there is no overarching state model that interrelates constructs within the different domains. This article reports 3 studies that provide converging evidence for 3 fundamental state dimensions labeled task engagement, distress, and worry that integrate constructs across the traditional domains. Study 1 differentiated the state dimensions by factor analysis of the scales of the Dundee Stress State Questionnaire (G. Matthews et al., 1999). Study 2 showed differential state response to performance of tasks making different cognitive demands. Study 3 showed that states are correlated with differing patterns of appraisal and coping. The 3 stress state dimensions provide a general descriptive framework consistent with transactional accounts of stress and performance.

Initial clinical validation of an embedded performance validity measure within the automated neuropsychological metrics (ANAM).

The measurement of effort and performance validity is essential for computerized testing where less direct supervision is needed. The clinical validation of an Automated Neuropsychological Metrics-Performance Validity Index (ANAM-PVI) was examined by converting ANAM test scores into a common metric based on their relative infrequency in an outpatient clinic sample with presumed good effort. Optimal ANAM-PVI cut-points were determined using receiver operator characteristic (ROC) curve analyses and an a priori specificity of 90%. Sensitivity/specificity was examined in available validation samples (controls, simulators, and neurorehabilitation patients). ANAM-PVI scores differed between groups with simulators scoring the highest. ROC curve analysis indicated excellent discriminability of ANAM-PVI scores ≥5 to detect simulators versus controls (area under the curve = 0.858; odds ratio for detecting suboptimal performance = 15.6), but resulted in a 27% false-positive rate in the clinical sample. When specificity in the clinical sample was set at 90%, sensitivity decreased (68%), but was consistent with other embedded effort measures. Results support the ANAM-PVI as an embedded effort measure and demonstrate the value of sample-specific cut-points in groups with cognitive impairment. Examination of different cut-points indicates that clinicians should choose sample-specific cut-points based on sensitivity and specificity rates that are most appropriate for their patient population with higher cut-points for those expected to have severe cognitive impairment (e.g., dementia or severe acquired brain injury).

Evidence for added value of baseline testing in computer-based cognitive assessment.

CONTEXT: Large-scale baseline cognitive assessment for individuals at risk for concussion is a common part of the protocol for concussion-surveillance programs, particularly in sports. Baseline cognitive testing is also being conducted in US military service members before deployment. Recently, the incremental validity of large-scale baseline cognitive assessment has been questioned. OBJECTIVE: To examine the added value of baseline cognitive testing in computer-based neuropsychological assessment by comparing 2 methods of classifying atypical performance in a presumed healthy sample. DESIGN: Cross-sectional study. SETTING: Military base. PATIENTS OR OTHER PARTICIPANTS: Military service members who took the Automated Neuropsychological Assessment Matrix (ANAM) before and after deployment (n = 8002). MAIN OUTCOME MEASURE(S): Rates of atypical performance in this healthy, active-duty sample were determined first by comparing postdeployment scores with a military normative database and then with each individual's personal baseline performance using a reliable change index. RESULTS: Overall rates of atypical performance were comparable across these 2 methods. However, these methods were highly discordant in terms of which individuals were classified as atypical. When norm-referenced methods were used, 2.6% of individuals classified as normal actually demonstrated declines from baseline. Further, 65.7% of individuals classified as atypical using norm-referenced scores showed no change from baseline (ie, potential false-positive findings). CONCLUSIONS: Knowing an individual's baseline performance is important for minimizing potential false-positive errors and reducing the risks and stresses of misdiagnosis.

Traditional neuropsychological correlates and reliability of the automated neuropsychological assessment metrics-4 battery for Parkinson's disease.

BACKGROUND: The automated neuropsychological assessment metrics battery-4 for PD offers the promise of a computerized approach to cognitive assessment. METHODS: To assess its utility, the ANAM4-PD was administered to 72 PD patients and 24 controls along with a traditional battery. Reliability was assessed by retesting 26 patients. RESULTS: The cognitive efficiency score (CES; a global score) exhibited high reliability (r = 0.86). Constituent variables exhibited lower reliability. The CES correlated strongly with the traditional battery global score, but displayed weaker relationships to UPDRS scores than the traditional score. Multivariate analysis of variance revealed a significant difference between the patient and control groups in ANAM4-PD performance, with three ANAM4-PD tests, math, tower, and pursuit tracking, displaying sizeable differences. In discriminant analyses these variables were as effective as the total ANAM4-PD in classifying cases designated as impaired based on traditional variables. Principal components analyses uncovered fewer factors in the ANAM4-PD relative to the traditional battery. ANAM4-PD variables correlated at higher levels with traditional motor and processing speed variables than with untimed executive, intellectual or memory variables. CONCLUSIONS: The ANAM4-PD displays high global reliability, but variable subtest reliability. The battery assesses a narrower range of cognitive functions than traditional tests, and discriminates between patients and controls less effectively. Three ANAM4-PD tests, pursuit tracking, math, and tower performed as well as the total ANAM4-PD in classifying patients as cognitively impaired. These findings could guide the refinement of the ANAM4-PD as an efficient method of screening for mild to moderate cognitive deficits in PD patients.

Cognitive change associated with self-reported mild traumatic brain injury sustained during the OEF/OIF conflicts.

Traumatic brain injury (TBI) has received much attention due to high rates of this injury in Service Members returning from the Iraq/Afghanistan conflicts. This study examined cognitive performance in Service Members tested with ANAM prior to and following deployment. The sample was divided into a control group (n=400) reporting no TBI injury prior to or during most recent deployment, and a group who self-reported a TBI injury (n=502) during most recent deployment. This latter group was divided further based on self-report of post-concussion symptoms at post-deployment testing. All three groups performed similarly at pre-deployment. The group reporting TBI with active symptoms performed worst at post-deployment and included the highest percentage of individuals showing significant decline in cognitive performance over time (30.5%). A small sample of symptomatic individuals with a non-TBI reported injury did not demonstrate similar declines in performance, suggesting that active symptoms alone cannot account for these findings. Of those reporting a TBI injury during deployment, 70% demonstrated no significant change in cognitive performance compared with baseline. Although the exact etiology of observed declines is uncertain, findings indicate that individuals who self-report TBI during deployment with active symptomatology at post-deployment are at greatest risk for declines in cognitive performance. These individuals can be identified using self-report and brief computer-based testing. Importantly, the majority of active-duty individuals reporting TBI during deployment do not present with lasting significant cognitive impairment, a finding consistent with the civilian literature on mild TBI.

Learning to live on a Mars day: fatigue countermeasures during the Phoenix Mars Lander mission.

STUDY OBJECTIVES: To interact with the robotic Phoenix Mars Lander (PML) spacecraft, mission personnel were required to work on a Mars day (24.65 h) for 78 days. This alien schedule presents a challenge to Earth-bound circadian physiology and a potential risk to workplace performance and safety. We evaluated the acceptability, feasibility, and effectiveness of a fatigue management program to facilitate synchronization with the Mars day and alleviate circadian misalignment, sleep loss, and fatigue. DESIGN: Operational field study. SETTING: PML Science Operations Center. PARTICIPANTS: Scientific and technical personnel supporting PML mission. INTERVENTIONS: Sleep and fatigue education was offered to all support personnel. A subset (n = 19) were offered a short-wavelength (blue) light panel to aid alertness and mitigate/reduce circadian desynchrony. They were assessed using a daily sleep/work diary, continuous wrist actigraphy, and regular performance tests. Subjects also completed 48-h urine collections biweekly for assessment of the circadian 6-sulphatoxymelatonin rhythm. MEASUREMENTS AND RESULTS: Most participants (87%) exhibited a circadian period consistent with adaptation to a Mars day. When synchronized, main sleep duration was 5.98 ± 0.94 h, but fell to 4.91 ± 1.22 h when misaligned (P < 0.001). Self-reported levels of fatigue and sleepiness also significantly increased when work was scheduled at an inappropriate circadian phase (P < 0.001). Prolonged wakefulness (≥ 21 h) was associated with a decline in performance and alertness (P < 0.03 and P < 0.0001, respectively). CONCLUSIONS: The ability of the participants to adapt successfully to the Mars day suggests that future missions should utilize a similar circadian rhythm and fatigue management program to reduce the risk of sleepiness-related errors that jeopardize personnel safety and health during critical missions.