Sport Contact Level Affects Post-Concussion Neurocognitive Performance in Young Athletes.

OBJECTIVE: Contact level affects the incidence of sports-related concussion. However, the effects of contact level on injury severity and recovery are less clear and are the focus of this study. METHOD: Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) for athletes aged 12-22 was performed at baseline (n = 10,907 for 7,058 athletes), after suspected concussion determined by physicians or athletic trainers (n = 5,062 for 4,419 athletes), and during follow-up visits (n = 3,264 for 2,098 athletes). Athletes played contact/collision (CC), limited contact (LC), and noncontact (NC) sports. Injury incidence, severity, and recovery were measured using raw and change from baseline neurocognitive test scores. Comparisons between groups used univariate analysis and multivariable regression controlling for demographic variables. RESULTS: Compared to CC athletes, LC and NC athletes showed decreased suspected concussion incidence. At initial post-injury testing, all neurocognitive test scores were similar between groups except changes from baseline for processing speed were improved for LC compared to CC athletes. Upon follow-up testing, raw neurocognitive scores were better for NC compared to the contact collision athletes in verbal memory, processing speed, total symptom score, migraine cluster, cognitive cluster, and neuropsychiatric cluster scores. For change from baseline scores, LC athletes exhibited better performance on verbal memory, processing speed, and reaction time but also showed higher neuropsychiatric scores than CC athletes. CONCLUSION: Neurocognitive scores between contact levels were similar at the first post-injury test. However, follow up showed many improved scores and symptoms for limited and NC sports compared to CC sports, which may indicate faster recovery.

Influence of Autism and Other Neurodevelopmental Disorders on Cognitive and Symptom Profiles: Considerations for Baseline Sport Concussion Assessment.

OBJECTIVE: The presence of neurodevelopmental disorders (ND) such as attention-deficit/hyperactivity disorder (ADHD) and learning disorders (LD) have demonstrated effects on Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) performance. No current research has directly examined whether autism spectrum disorder (ASD) has similar effects. The current study compared ImPACT cognitive and symptom profiles in athletes with self-reported ASD to other NDs and healthy controls using case-control matching. METHOD: The current study compared ImPACT baselines of high school athletes with ASD to athletes with other NDs (ADHD, LD, and co-occurring ADHD/LD) and healthy controls on cognitive composites and symptom reporting. Participants included 435 athletes (87 controls, 87 with ASD, 87 with ADHD, 87 with LD, and 87 with ADHD/LD) selected from a larger naturalistic sample. Athletes were matched to the ASD group based on age, sex, and sport using randomized case-matched selection from the larger database. RESULTS: Results revealed that athletes with ASD performed more poorly than healthy controls on the Visual Motor Speed composite. No differences were found for Post-concussion Symptom Scale (PCSS) domain scores. Differences in cognitive and symptom profiles among the athletes with other NDs were also found. CONCLUSIONS: Results elucidate patterns of baseline performance for athletes with ASD, demonstrating that there may not be significant differences between ASD and healthy controls on four of the five ImPACT composites, and no symptom reporting differences. Cognitive and symptom differences found for other NDs should be considered when interpreting baseline performance and for making return-to-play decisions in the absence of baseline assessment.

Epidemiology of traumatic brain injury in children 15 years and younger in South-Eastern Norway in 2015-16. Implications for prevention and follow-up needs.

OBJECTIVE: This retrospective study aimed to describe the volume, severity, and injury mechanism of all hospital-admitted pediatric traumatic brain injury (pTBI) at Oslo University Hospital (OUH), emphasizing consequences for prevention and factors indicating a need for follow-up programs. METHOD: Data were extracted from the OUH Trauma registry on 176 children, 0-15 years old, admitted to OUH in 2015 and 2016 with a pTBI diagnosis. The dataset contains demographic data, injury mechanism, type, and severity (Glasgow coma scale, GCS; abbreviated injury scale, AIS; injury severity score, ISS), ICD-10 diagnosis codes, level of treatment, and destination of discharge. RESULTS: 79.5% had mild, 9% moderate, and 11.4% severe TBI. The incidence of hospital-treated pTBI in Oslo was 29 per 100,000 per year. The boy: girl ratio was 1.9:1, but in the young teenage group (14-15 years), the ratio was 1:1. Intracranial injury (ICI) identified on CT/MRI was associated with extended hospital stays, with a median of 6 days compared to 1 day for patients without ICI. 27% of the patients assessed as mild TBI at admission had ICI. Children below eight years of age had a higher incidence of moderate and severe ICI from trauma (53% v.s. 28% in children ≥ eight years). CONCLUSION: The injury characteristics of hospital-treated pTBI are in line with other European countries, but we find the boy-girl ratio different as young teenage girls seem to be catching up with the boys. ICI and length of stay should be considered when deciding which patients need follow-up and rehabilitation.

Internal (Factorial) Validity of the ANAM using a Cohort of Woman High-School Soccer Players.

INTRODUCTION: Computerized neuropsychological testing is a cornerstone of sport-related concussion assessment. Female soccer players are at an increased risk for concussion as well as exposures to repetitive head impacts from heading a soccer ball. Our primary aim was to examine factorial validity of the Automated Neuropsychological Assessment Metrics (ANAM) neuropsychological test battery in computing the multiple neurocognitive constructs it purports to measure in a large cohort of interscholastic female soccer players. METHODS: Study participants included 218 interscholastic female soccer players (age = 17.0±0.7 year; mass = 55.5±6.8 kg; height = 164.7±6.6 cm) drawn from a large (850+) prospective database examining purposeful heading from four area high schools over a 10-year period. The ANAM-2001 measured neurocognitive performance. Three methods were used to identify integral constructs underlying the ANAM: (a) exploratory factor analysis (EFA), (b) first-order confirmatory factor analysis (CFA), and (c) hierarchical CFA. RESULTS: Neuropsychological phenomena measured by the ANAM-2001 were best reproduced by a hierarchical CFA organization, composed of two lower level factors (Simple Reaction Time, Mental Efficiency) and a single, general composite. Although the ANAM was multidimensional, only the composite was found to possess sufficient construct dimensionality and reliability for clinical score interpretation. Findings failed to uphold suppositions that the ANAM measures seven distinct constructs, or that any of its seven tests provide unique information independent of other constructs, or the composite, to support individual interpretation. CONCLUSIONS: Outcomes infer the ANAM possesses factorial-validity evidence, but only scores from the composite appear to sufficiently internally valid, and reliable, to support applied use by practitioners.

Comparing Composite Scores for the ANAM4 TBI-MIL for Research in Mild Traumatic Brain Injury.

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 <50th, ≤16th percentile, or ≤5th percentile; and the ANAM Composite Score (ACS). 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.

Measuring Change in Symptoms of Neurobehavioural Disability: Responsiveness of the St Andrew's-Swansea Neurobehavioural Outcome Scale.

OBJECTIVE: Neurobehavioural disability (NBD) after acquired brain injury (ABI) is often associated with poor outcome. The "St Andrew's-Swansea Neurobehavioural Outcome Scale" (SASNOS) was developed to measure NBD in a range of applications. Two of the "holy trinity" of psychometric properties, reliability and validity, have been comprehensively mapped, but the extent to which SASNOS meets the third, responsiveness, has not been investigated. Demonstrating responsiveness is essential in instruments employed in repeated measurement scenarios to confirm their ability to discriminate real change from error. However, there is no single agreed method for determining responsiveness. For some instruments, this property remains unexplored. A difference in scores attaining statistical significance for aggregate data is frequently cited as support for this construct, but this approach remains heavily criticized. This study explores responsiveness of SASNOS. METHOD: Consecutive SASNOS assessments completed over varying times for 145 individuals participating in neurobehavioural rehabilitation, drawn from multiple services, were compiled into a retrospective sample of convenience. Multiple methods were employed to confirm internal responsiveness, including those identifying statistically significant change, minimally detectable change and minimally important change. RESULTS: All methods confirmed responsiveness as a psychometric property of SASNOS; the extent depended on method used and NBD domain investigated. A number of indicators are presented, which equip clinicians and researchers with options to interpret results from repeated assessments, including the individual level in the context of rehabilitation. CONCLUSIONS: SASNOS reliably measures change over time in NBD symptoms, further confirming its suitability as an instrument for investigating multidimensional outcomes of ABI.

Relative Utility of Performance and Symptom Validity Tests.

This investigation adds to the burgeoning body of research concerned with discriminating performance and symptom validity tests (SVTs) through examination of their differential relationships with cognitive performance and symptom self-report measures. To the authors' current knowledge, prior studies have not assessed differences between participants who fail either a performance validity test (PVT) or an SVT but not both. As part of their neuropsychological evaluations at four Veterans Affairs medical centers across the United States, participants were administered a fixed, standardized battery that consisted of performance validity, symptom validity, cognitive performance, and symptom self-report measures. Compared with participants who failed a PVT and an SVT, participants who passed both and participants who only passed a PVT demonstrated better cognitive performance and self-reported fewer symptoms. Results support differential clinical utility of performance validity and SVTs when assessing cognitive performance and symptom self-report.

A Factor Analytic Approach to the Validation of the Word Memory Test and Test of Memory Malingering as Measures of Effort and Not Memory.

Research has demonstrated the utility of performance validity tests (PVTs) as a method of determining adequate effort during a neuropsychological evaluation. Although some studies affirm that forced-choice PVTs measure effort rather than memory, doubts remain in the literature. The purpose of the current study was to evaluate the relationship between effort and memory variables in a mild traumatic brain injury (TBI) sample (n = 160) by separating memory and effort as distinct factors while statistically controlling for the shared covariance between the variables. A two-factor solution was extracted such that the five PVT variables loaded on Factor 1 and the four memory variables loaded on Factor 2. The pattern matrix, which controls for the covariance between variables, provided clear support of two highly distinct factors with minimal cross-loadings. Our findings support assertions that PVTs measure effort independent of memory in veterans with mild TBI.

FMRI hypoactivation during verbal learning and memory in former high school football players with multiple concussions.

Multiple concussions before the age of 18 may be associated with late-life memory deficits. This study examined neural activation associated with verbal encoding and memory retrieval in former athletes ages 40-65 who received at least two concussions (median = 3; range = 2-15) playing high school football and a group of former high school football players with no reported history of concussions matched on age, education, and pre-morbid IQ. Functional magnetic resonance imaging data collected during a modified verbal paired associates paradigm indicated that those with concussive histories had hypoactivation in left hemispheric language regions, including the inferior/middle frontal gyri and angular gyrus compared with controls. However, concussive history was not associated with worse memory functioning on neuropsychological tests or worse behavioral performance during the paradigm, suggesting that multiple early-life concussions may be associated with subtle changes in the verbal encoding system that limits one from accessing higher-order semantic networks, but this difference does not translate into measurable cognitive performance deficits.