Long-term test-retest reliability of baseline cognitive assessments using ImPACT

Long-term test-retest reliability of the vestibular/ocular motor screening for concussion in child athletes: A preliminary study

The Vestibular/Ocular Motor Screening (VOMS) is a sport-related concussion screening tool that assesses vestibular ocular reflex (VOR) and oculomotor symptom provocation. Long-term test-retest reliability of the VOMS over multiple athletic seasons has not yet been established in a pediatric population. Fifty-one child athletes (females = 28, 54.9%) 8-13 years of age, completed a baseline VOMS assessment at two timepoints, 18 months apart. Cronbach's alpha was used to examine the internal consistency at both time points. Two-way mixed intra-class correlation coefficients and Cohen's Kappa statistics were used to evaluate test-retest reliability. High internal consistency existed at both initial (α = 0.91) and follow-up (α = 0.95) for VOMS symptom provocation items. Strong inter-item correlations were noted between vertical VOR (r = ≥0.70) and visual motion sensitivity (VMS) (r = ≥0.70). Fair agreement was produced for convergence (κ = 0.23, vertical VOR (κ = 0.25) and VMS (κ = 0.25), as well as reliability on NPC distance (ICC2,k = 0.31). All other VOMS scores yielded poor agreement between time points. Symptom provocation was the same for 49% of athletes between timepoints, while 31.4% had a decrease in scoring at follow-up. Symptom provocation from VOMS tasks lessened with increasing age and time; therefore, clinicians should consider annual baseline testing to improve accuracy for concussion evaluation and management in pediatrics.

The role of concussion history and biological sex on baseline concussion clinical profile symptoms in adolescent rugby players

BACKGROUND

Accurate concussion monitoring requires access to preinjury baseline data. This is particularly important in adolescent athletes who have a high risk of concussion and are prone to prolonged recovery. As Rugby Union is governed by similar laws for men and women, it is also an ideal population to rigorously examine the impact of biological sex on concussion symptoms.

AIMS

To evaluate self-reported concussion symptoms at baseline in adolescent rugby union players, and examine if subtype-specific symptoms are affected by concussion history and biological sex.

METHODS

Adolescent rugby union players aged 16-18 years were recruited during the 2022-2023 playing season. Participants completed a series of questionnaires covering post-concussion symptoms, concussion clinical profiles, anxiety, depression and fear avoidance behaviours. Independent variables of interest in analysis were biological sex and concussion history.

RESULTS

149 participants (75% male) were included. 42% (63/149) reported at least one previous concussion (average time since concussion: 18.7 months, range 1-72). Adolescents with a concussion history reported significantly higher scores than those with no history, across two clinical profiles (ocular and sleep), concussion symptom severity, and depression, all based on medium effect sizes (SMD 0.3-0.5). Females had significantly higher scores across cognitive/fatigue, ocular and sleep clinical profiles, concussion symptoms, anxiety and depression, each with large effect sizes (SMD > 0.5).

CONCLUSIONS

Concussion history and sex are associated with higher baseline scores on specific concussion clinical profile, concussion symptom severity, and anxiety symptoms. These findings highlight the importance of considering baseline differences when interpreting post-injury clinical profile symptoms in adolescent rugby players. (Trial registration: ACTRN12622000931774).

Psychometric Properties of Computerized Cognitive Tools and Standard Neuropsychological Tests Used to Assess Sport Concussion: A Systematic Review

Athletic programs are more frequently turning to computerized cognitive tools in order to increase efficiencies in concussion assessment. However, assessment using a traditional neuropsychological test battery may provide a more comprehensive and individualized evaluation. Our goal was to inform sport clinicians of the best practices for concussion assessment through a systematic literature review describing the psychometric properties of standard neuropsychological tests and computerized tools. We conducted our search in relevant databases including Ovid Medline, Web of Science, PsycINFO, and Scopus. Journal articles were included if they evaluated psychometric properties (e.g., reliability, sensitivity) of a cognitive assessment within pure athlete samples (up to 30 days post-injury). Searches yielded 4,758 unique results. Ultimately, 103 articles met inclusion criteria, all of which focused on adolescent or young adult participants. Test-retest reliability estimates ranged from .14 to .93 for computerized tools and .02 to .95 for standard neuropsychological tests, with strongest correlations on processing speed tasks for both modalities, although processing speed tasks were most susceptible to practice effects. Reliability was improved with a 2-factor model (processing speed and memory) and by aggregating multiple baseline exams, yet remained below acceptable limits for some studies. Sensitivity to decreased cognitive performance within 72 h of injury ranged from 45%-93% for computerized tools and 18%-80% for standard neuropsychological test batteries. The method for classifying cognitive decline (normative comparison, reliable change indices, regression-based methods) affected sensitivity estimates. Combining computerized tools and standard neuropsychological tests with the strongest psychometric performance provides the greatest value in clinical assessment. To this end, future studies should evaluate the efficacy of hybrid test batteries comprised of top-performing measures from both modalities.

Neck Symptoms and Associated Clinical Outcomes in Patients Following Concussion

OBJECTIVE

To examine the frequency and association of neck pain symptoms in patients with a concussion.

STUDY SETTING AND PARTICIPANTS

Three-hundred and thirty-one consecutively enrolled patients aged 9 to 68 years with a diagnosed concussion 1 to 384 days post-injury were enrolled at a concussion clinic from a single integrated healthcare system in Western Pennsylvania between 2019 and 2021.

DESIGN

Retrospective cohort analysis of prospectively collected concussion screening tool intake survey responses and clinical outcomes data. The primary outcome was self-reported neck pain or difficulty with neck movement on the Concussion Clinical Profiles Screening (CP Screen) tool, recovery time, and incidence of treatment referral. Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) composite scores, Vestibular/Ocular Motor Screening (VOMS) item scores, type and severity of neck symptoms, mechanism of injury, time from injury to clinic presentation, medical history, and concussion symptom profile were secondary outcomes.

RESULTS

Of the 306 consecutively enrolled eligible patients in the registry, 145 (47%) reported neck pain, 68 (22.2%) reported difficulty moving their neck, and 146 (47.7%) reported either symptom. A total of 47 (15.4%) participants reported more severe neck symptoms, and this group took longer to recover (40 ± 27 days) than those not reporting neck symptoms (30 ± 28 days; U = 8316, P < .001). Stepwise logistic regression predicting more severe neck symptoms was significant (Nagelkerke R2 = 0.174, χ 2 = 9.315, P = .316) with older age ( P = .019) and mechanism of injury including motor vehicle collisions (MVCs) ( P = .047) and falls ( P = .044) as risk factors. MVCs and falls were associated with over 4 times and 2 times greater risk, respectively, for reporting more severe neck symptoms.

CONCLUSION

Neck pain and stiffness symptoms are common in patients with a concussion following high-energy mechanisms of injury including MVCs or falls from height. These symptoms are associated with prolonged recovery. Providers should evaluate neck symptoms and consider targeted treatment strategies to limit their effects in patients with a concussion.

Assessing blood oxygen level-dependent signal variability as a biomarker of brain injury in sport-related concussion

Mild traumatic brain injury is a complex neurological disorder of significant concern among athletes who play contact sports. Athletes who sustain sport-related concussion typically undergo physical examination and neurocognitive evaluation to determine injury severity and return-to-play status. However, traumatic disruption to neurometabolic processes can occur with minimal detectable anatomic pathology or neurocognitive alteration, increasing the risk that athletes may be cleared for return-to-play during a vulnerable period and receive a repetitive injury. This underscores the need for sensitive functional neuroimaging methods to detect altered cerebral physiology in concussed athletes. The present study compared the efficacy of Immediate Post-concussion Assessment and Cognitive Testing composite scores and whole-brain measures of blood oxygen level-dependent signal variability for classifying concussion status and predicting concussion symptomatology in healthy, concussed and repetitively concussed athletes, assessing blood oxygen level-dependent signal variability as a potential diagnostic tool for characterizing functional alterations to cerebral physiology and assisting in the detection of sport-related concussion. We observed significant differences in regional blood oxygen level-dependent signal variability measures for concussed athletes but did not observe significant differences in Immediate Post-concussion Assessment and Cognitive Testing scores of concussed athletes. We further demonstrate that incorporating measures of functional brain alteration alongside Immediate Post-concussion Assessment and Cognitive Testing scores enhances the sensitivity and specificity of supervised random forest machine learning methods when classifying and predicting concussion status and post-concussion symptoms, suggesting that alterations to cerebrovascular status characterize unique variance that may aid in the detection of sport-related concussion and repetitive mild traumatic brain injury. These results indicate that altered blood oxygen level-dependent variability holds promise as a novel neurobiological marker for detecting alterations in cerebral perfusion and neuronal functioning in sport-related concussion, motivating future research to establish and validate clinical assessment protocols that can incorporate advanced neuroimaging methods to characterize altered cerebral physiology following mild traumatic brain injury.

Combined Neurocognitive and Exercise Tolerance Testing Improves Objectivity of Buffalo Concussion Treadmill Test

CONTEXT

The Buffalo Concussion Treadmill Test (BCTT) is a standard assessment of exercise tolerance utilized for exercise prescription following concussion and to inform decisions regarding return to play. One limitation of the BCTT is that interpretation of test results is dependent on individuals' self-report of symptom exacerbation with exertion. Symptoms following concussion are significantly underreported or unreported. Combining objective neurocognitive assessment with exercise tolerance testing may enable clinicians to objectively identify those requiring further assessment or rehabilitation before return to play. The purpose of this study was to investigate how performance on a neurocognitive assessment battery is affected by provocative exercise testing.

DESIGN

Prospective cohort study, pretest/posttest.

METHODS

A total of 30 participants included 13 women (43.3%), age 23.4 (1.93) years, height 173.56 (10) cm, weight 77.35 (16.3) kg, and 11 (36.7%) with history of concussion. All participants completed a neurocognitive assessment battery, including the Stroop Test and standardized assessments of working memory, attention, and information processing speed/accuracy in single-task (seated position) and dual-task conditions (walking on a treadmill at 2.0 miles per hour). The neurocognitive assessment battery was performed at baseline and after the standard BCTT test protocol.

RESULTS

BCTT: Average percentage of heart rate maximum (%HRmax) = 93.97% (4.8%); average maximum rating of perceived exertion = 18.6 (1.5). Time-based performance in single-task and dual-task conditions significantly improved from baseline (P < .05) following maximal exercise testing on the BCTT for the following neurocognitive assessments: concentration-reverse digits, Stroop congruent, and Stroop incongruent.

CONCLUSIONS

Healthy participants demonstrated improvements across multiple domains of neurocognitive performance following the exercise tolerance testing on the BCTT. Understanding normal responses in neurocognitive performance for healthy individuals following exercise tolerance testing may allow clinicians to more objectively monitor the trajectory of recovery following sports-related concussion.

A multicenter, longitudinal survey of headaches and concussions among youth athletes in the United States from 2009 to 2019

OBJECTIVE/ BACKGROUND

Chronic headaches and sports-related concussions are among the most common neurological morbidities in adolescents and young adults. Given that the two can overlap in presentation, studying the effects of one on another has proven difficult. In this longitudinal study, we sought to assess the relationship between chronic headaches and concussions, analyzing the role of historic concussions on chronic headaches, as well as that of premorbid headaches on future concussion incidence, severity, and recovery.

METHODS

This multi-center, longitudinal cohort study followed 7,453 youth athletes who were administered demographic and clinical surveys as well as a total of 25,815 Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) assessments between 2009 and 2019. ImPACT was administered at baseline. Throughout the season concussions were examined by physicians and athletic trainers, followed by re-administration of ImPACT post-injury (PI), and at follow-up (FU), a median of 7 days post-concussion. Concussion incidence was calculated as the total number of concussions per patient years. Concussion severity and recovery were calculated as standardized deviations from baseline to PI and then FU in Symptom Score and the four neurocognitive composite ImPACT scores: Verbal Memory, Visual Memory, Processing Speed, and Reaction Time. Data were collected prospectively in a well-organized electronic format supervised by a national research-oriented organization with rigorous quality assurance. Analysis was preformed retrospectively.

RESULTS

Of the eligible athletes, 1,147 reported chronic headaches (CH) at the start of the season and 6,306 reported no such history (NH). Median age of the cohort was 15.4 ± 1.6 years, and students were followed for an average of 1.3 ± 0.6 years. A history of concussions (OR 2.31, P < 0.0001) was associated with CH. Specifically, a greater number of past concussions (r2 = 0.95) as well as concussions characterized by a loss of consciousness (P < 0.0001) were associated with more severe headache burden. The CH cohort had a greater future incidence of concussion than the NH cohort (55.6 vs. 43.0 per 100 patient-years, P < 0.0001). However, multivariate analysis controlling for demographic, clinical, academic, and sports-related variables yielded no such effect (OR 0.99, P = 0.85). On multivariable analysis the CH cohort did have greater deviations from baseline to PI and FU in Symptom Score (PI OR per point 1.05, P = 0.01, FU OR per point 1.11, P = 0.04) and Processing Speed (OR per point 1.08, P = 0.04), suggesting greater concussion severity and impaired symptomatic recovery as compared to the NH cohort.

CONCLUSION

A history of concussions was a significant contributor to headache burden among American adolescents and young adults. However, those with chronic headaches were not more likely to be diagnosed with a concussion, despite presenting with more severe concussions that had protracted recovery. Our findings not only suggest the need for conservative management among youth athletes with chronic headaches, they also indicate a potential health care gap in this population, in that those with chronic headaches may be referred for concussion diagnosis and management at lower rates than those with no such comorbidity.

Changes in ImPACT Cognitive Subtest Networks Following Sport-Related Concussion

OBJECTIVE

High school athletes are administered ImPACT at the start of the academic year or sport season and again after suspected concussion. Concussion management involves the comparison of baseline and post-injury cognitive scores with declines in scores providing evidence for concussive injury. A network framework may provide additional information about post-concussive cognitive changes and expand characterization of sport-related concussion (SRC) recovery.

DESIGN

Retrospective cohort study.

SETTING

High school.

PARTICIPANTS

High school athletes (n = 1553) were administered ImPACT at baseline (T1), post-SRC (T2 = 72 h of injury), and prior to return to play (T3 = within two weeks post-injury).

INDEPENDENT VARIABLES

ImPACT cognitive subtest scores.

MAIN OUTCOME MEASURES

Cognitive networks were calculated and compared over three time points. Centrality indices were calculated to determine the relative importance of cognitive variables within networks.

RESULTS

Network connectivity increased from T1 to T2 and remained hyperconnected at T3. There was evidence of network reorganization between T1 and T3. Processing speed was central within each network, and visual memory and impulsivity became more central over time.

CONCLUSIONS

The results suggest potential evidence of cognitive network change over time. Centrality findings suggest research specific to visual memory and impulse control difficulties during the post-concussion recovery period is warranted. Network analysis may provide additional information about cognitive recovery following SRC and could potentially serve as an effective means of monitoring persisting cognitive symptoms after concussion.

The Post-Concussion Symptom Scale: Normative Data for Adolescent Student-Athletes Stratified by Gender and Preexisting Conditions

BACKGROUND

The Post-Concussion Symptom Scale (PCSS) is a self-report questionnaire measuring symptoms that commonly occur after a concussion; however, these symptoms are nonspecific and can be related to co-occurring orthopaedic injuries (eg, cervical strain) or patient characteristics and preexisting conditions, even in the absence of a recent injury. As such, clinicians may have difficulty determining whether symptom elevations are attributable to a recent concussion as opposed to a confounding injury or a preexisting condition, which may be especially difficult when preinjury baseline symptom data are unavailable.

PURPOSE

This study aimed to further validate the 4-factor model of the PCSS (ie, cognitive, sleep-arousal, physical, and affective symptoms) with adolescent student-athletes and provide normative reference data for each factor and the total score, stratified by gender and preexisting health conditions.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Participants were 9358 adolescent student-athletes who completed the PCSS during a preseason baseline evaluation (mean age, 14.9 years; SD, 1.3 years [range, 13-18 years]; 49.3% boys). The 4-factor model of the PCSS was tested for the full sample and separately for boys and girls using confirmatory factor analysis. Symptom severity percentiles were created for the PCSS total score and each factor, stratified by gender and preexisting conditions (ie, attention-deficit/hyperactivity disorder, mental health history, headache/migraine history, learning disability/dyslexia, academic problems, and concussion history).

RESULTS

The 4-factor model of the PCSS replicated in the full sample (comparative fit index [CFI] = 0.959) and in both gender groups (boys: CFI = 0.961; girls: CFI = 0.960). The total PCSS score at the 84th percentile varied by preexisting conditions as follows: healthy participants = 8, attention-deficit/hyperactivity disorder = 18, mental health history = 26, headache/migraine history = 18, learning disability = 19, and academic problems = 17. On all PCSS subscales, participants with a mental health history had the highest scores, and high scores were associated with having >1 preexisting condition. Girls had higher scores than boys for each stratification.

CONCLUSION

The 4-factor model of the PCSS replicates for adolescent student-athletes. Gender, number of preexisting conditions, and mental health history are important factors to account for when interpreting PCSS symptom severity. The normative data provided herein could assist clinicians in determining whether an adolescent student-athlete is presenting with persistent postconcussion symptoms or a typical symptom experience based on their gender and personal health history.

Test-Retest Reliability and Efficacy of Individual Symptoms in Concussion Management

OBJECTIVE

(1) To determine test-retest reliability of individual Sport Concussion Assessment Tool-Third Edition (SCAT-3) symptom scores and symptom severity scores, (2) to examine the specificity/sensitivity of individual SCAT-3 symptom severity scores acutely (24-48 hours) postconcussion, and (3) to develop a model of symptoms best able to differentiate concussed from nonconcussed student athletes and cadets.

DESIGN

Prospective, longitudinal, and cross-sectional.

SETTING

Twenty-six civilian schools and 3 US service academies.

PARTICIPANTS

Collegiate student athletes (n = 5519) and cadets (n = 5359) from the National Collegiate Athletic Association-Department of Defense Grand Alliance: Concussion Assessment, Research and Education Consortium, including 290 student athletes and 205 cadets, assessed 24 to 48 hours postconcussion.

INDEPENDENT VARIABLES

Concussed and nonconcussed student athlete and cadet groups.

MAIN OUTCOME MEASURES

Sport Concussion Assessment Tool-Third Edition individual symptom severity scores, total symptom scores, and symptom severity scores.

RESULTS

Results indicated poor test-retest reliability across all symptom scores (intraclass correlation coefficient = 0.029-0.331), but several individual symptoms had excellent predictive capability in discriminating concussed from nonconcussed participants (eg, headache, pressure in the head, and don't feel right had area under the curve >0.8, sensitivity >70%, and specificity >85%) regardless of baseline testing. These symptoms were consistent with Chi-square Automatic Interaction Detector classification trees with the highest mean probability.

CONCLUSIONS

Findings support the excellent diagnostic accuracy of honest symptom reporting, notwithstanding the known limitations in symptom underreporting, and suggest that there may be added value in examining individual symptoms rather than total symptom scores and symptom severity scores alone. Finally, findings suggest that baseline testing is not necessary for interpreting postconcussion symptom scores.

Symptom Provocation Following Post-concussion Computerized Neurocognitive Testing and Its Relationship to Other Clinical Measures of Concussion

OBJECTIVE

The objective of this study was to document the prevalence of post-computerized neurocognitive test (post-CNT) increases in symptoms in athletes with sport-related concussion, and to examine the effect of post-CNT symptom increases on concussion neurocognitive and vestibular/ocular motor clinical outcomes.

METHODS

This was a retrospective analysis of medical records from a concussion specialty clinic. Two hundred and three athletes (M = 16.48 ± 1.97 years; 44% [90/203] female) completed a clinical visit for concussion within 30 days of injury (M = 7.73 ± 5.54 days). Computerized neurocognitive testing (the Immediate Post-concussion Assessment and Cognitive Testing: ImPACT), the Post-Concussion Symptom Scale (PCSS), and the Vestibular Ocular Motor Screening (VOMS) were the main outcome measures for the current study.

RESULTS

Sixty-nine percent (141/203) of the sample did not report significant increases in PCSS scores following post-concussion CNT and were classified into a No Provocation (NO PROV) group. Thirty-one percent (62/203) of participants did report a significant increase in symptoms following post-concussion CNT and were classified into a Provocation (PROV) group. Neurocognitive performance was similar between groups. However, the PROV group reported significantly higher scores on the VOMS symptom items than the NO PROV group.

CONCLUSIONS

The majority of adolescent athletes can complete a post-concussion CNT without experiencing significant increases in concussion symptoms. Individuals that report symptom increases from completing a post-concussion CNT are more likely to exhibit increased vestibular/ocular motor symptoms. These findings underscore the relationship between the clinical findings from both CNT and vestibular/ocular motor measures following concussion.

Test-retest reliability of the neurotracker compared to the impact test for the management of mild traumatic brain injuries during two consecutive university sport seasons

INTRODUCTION

Neurocognitive assessment tools such as the Neurotracker and ImPACT have been proposed to optimize sports-related mild traumatic brain injury (mTBI) management. Baseline testing is recommended with such assessments to individualize monitoring of athletes' remission. While the ideal timeframe between baseline updates has been studied for the ImPACT, these data are missing for the Neurotracker.

OBJECTIVE

The current study aimed to compare the test-retest reliability of the ImPACT and Neurotracker for two consecutive seasons in university athletes participating in sports at risk for mTBI.

METHODS

At the start of two consecutive seasons, 30 athletes with no recent history of mTBI completed a baseline assessment including the Neurotracker and the ImPACT. The test-retest reliability of the results was analyzed by considering intra-class correlation (ICC), Becker's standardized mean difference (d_B) and Bland-Altman' plot of each outcome.

RESULTS

The Neurotracker and the Visual Motor Speed composite score of the ImPAC were the only outcomes with significative ICCs and acceptable d_B between the two seasons. Neurotracker was the only outcome with a significative bias (+0.179).

CONCLUSION

Our research suggests that the Neurotracker has an acceptable level of test-retest reliability after one year in comparison to the ImPACT.

Test-Retest Reliability of Remote ImPACT Administration

OBJECTIVE

To evaluate the performance and test-retest reliability obtained when administering a computerized baseline neurocognitive exam to NCAA Division I student-athletes in a controlled laboratory setting versus an uncontrolled remote location.

METHOD

A sample of 129 (female = 100) Division I student-athletes completed Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) pre-season assessments for two distinct and respective sports seasons in a controlled laboratory environment and an uncontrolled remote environment. Depending on the environment, participants were given verbal (controlled) or written (uncontrolled) guidelines for taking the test.

RESULTS

Multivariate repeated-measures ANOVA's determined that there were no within-subject differences between testing environments on ImPACT composite scores and cognitive efficiency index (CEI). The Chi-square test did not find any significant differences in impulse control or the number of invalid test scores, as determined by ImPACT, between environments. Intraclass correlations found the ImPACT subtest scores to range in test-retest reliability across testing environments, demonstrating moderate (verbal memory composite, r = 0.46; visual memory composite, r = 0.64; reaction time, r = 0.61; impulse control, r = 0.52; and CEI, r = 0.61) and good (visual motor composite, r = 0.77) test-retest reliability.

CONCLUSIONS

Results indicate that ImPACT is reliable between controlled and uncontrolled testing environments. This further suggests that ImPACT can be administered in a remote environment, pending specific adherence to testing instructions, or in the event of social distancing or isolation policies.

Incidence and Severity of Concussions Among Young Soccer Players Based on Age, Sex, and Player Position

Background:

Previously studied risk factors for sports-related concussion in soccer players include sex, age, and player position. However, prior studies were limited in number, they reported conflicting results, and most did not assess initial concussion severity.

Purpose/Hypothesis:

The purpose of this study was to conduct an in-depth analysis of soccer players across key demographic groups (sex, age, position) for both concussion incidence and severity. It was hypothesized that concussion incidence and severity would be higher among male players, players aged ≥17 years, and goalkeepers.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

The authors analyzed baseline and postinjury ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) scores for athletes aged 12 to 22 years between July 2009 and June 2019. Players were assigned to an age group based on when they had their most recent baseline test. Concussion incidence and concussion severity index were compared using t tests and multivariate logistic regression.

Results:

For 1189 individuals who reported soccer as their primary sport, 1032 contributed 1754 baseline ImPACT tests (some individuals had multiple baseline tests), whereas 445 individuals were suspected of sustaining a concussion and then referred for a postinjury 1 test. Of these players, 254 (24.6%) had both a baseline and a postinjury test and were analyzed for concussion severity. Linear regression showed that forwards had a lower incidence of ImPACT-proxied concussions than goalkeepers had (P = .008). Female players had a significantly higher incidence of ImPACT concussions compared with male players (mean, 0.07 [female] vs 0.04 [male] concussions per person-year; P = .05). Players in the ≥17-year age group had a higher incidence of ImPACT concussions than players in the 15- to 16-year age group (P = .04), although the 15- to 16-year age group had more severe concussions than the ≥17-year age group (mean severity index, 2.91 [age 15-16 years] vs 1.73 [age ≥17 years]; P = .001).

Conclusion:

Female soccer players experienced a higher incidence of concussion than did male players, and goalkeepers experienced a greater incidence of ImPACT concussions than did forwards. Players of both sexes and all positions in the 15- to 16-year age group showed increased initial concussion severity compared with the ≥17-year age group, despite a lower comparative incidence of ImPACT concussions. Further study is needed to understand whether sex and player position affect concussion severity.

Visual cognition associated with knee proprioception, time to stability, and sensory integration neural activity after ACL reconstruction

Visual cognitive ability has previously been associated with anterior cruciate ligament injury and injury risk biomechanics in healthy athletes. Neuroimaging reports have identified increased neural activity in regions corresponding to visual-spatial processing, sensory integration, and visual cognition in individuals after anterior cruciate ligament reconstruction (ACLR), indicating potential neural compensatory strategies for motor control. However, it remains unclear whether there is a relationship between visual cognition, neural activity, and metrics of neuromuscular ability after ACLR. The purpose of this study was to (1) evaluate the relationship between visual cognitive function and measurements of neuromuscular control (proprioception and time to stability [TTS]), isokinetic strength, and subjective function, and (2) examine the neural correlates of visual cognition between ACLR (n = 16; time since surgery 41.4 ± 33.0 months) and demographically similar controls (n = 15). Visual cognition was assessed by the ImPACT visual motor and visual memory subscales. Outcome variables of proprioception to target knee angle 20°, landing TTS, strength, and subjective function were compared between groups, and visual cognition was correlated within groups to determine the relationship between visual cognition and outcome variables controlled for time from surgery (ACLR group). The control group had better IKDC scores and strength. Visual memory and visual motor ability were negatively associated with proprioception error (r = -0.63) and TTS (r = -0.61), respectively, in the ACLR group but not controls. Visual cognition was associated with increased neural activity in the precuneus and posterior cingulate cortex in the ACLR group but not control participants. These data suggest the neural strategy in which ACLR participants maintain proprioception and stability varies, and may depend on visual cognition and sensory integration neural activity.

Influence of Sleep Dysfunction on Concussion Assessment Outcomes Among Adolescent Athletes After Concussion and Healthy Controls

BACKGROUND

Sleep dysfunction (SD) is associated with a high symptom burden and lower neurocognitive performance after concussion and on baseline testing without injury. However, few studies have compared concussed athletes and controls with and without SD on clinical outcomes.

OBJECTIVE

To evaluate differences in clinical outcomes among both concussed athletes and matched controls with and without SD.

DESIGN

Retrospective cross-sectional study.

PARTICIPANTS

Participants aged 12 to 20 years were recruited from a concussion clinic (n = 50 patients) and research registry/flyers (n = 50 healthy age-/sex-matched controls). Participants were categorized by self-reported SD into one of 4 groups: sport-related concussion (SRC) + SD, SRC only, SD only, and controls.

MAIN OUTCOME MEASURES

Post-Concussion Symptom Scale (PCSS), Vestibular/Oculomotor Screening (VOMS), and neurocognitive testing (Immediate Postconcussion Assessment Cognitive Test).

RESULTS

Compared with the SRC only group, the SRC + SD group performed worse on all neurocognitive domains, had a higher total symptom score, and endorsed more symptoms on most VOMS items. In addition, the SRC + SD group was at an increased likelihood of having at least 1 abnormal VOMS item compared with SRC only group. The SRC only group had neurocognitive test scores and symptom reports statistically similar to the SD only group.

CONCLUSION

Sleep dysfunction after concussion is related to worse neurocognitive performance and higher concussion symptom reporting. This study extended findings to suggest vestibular symptomology is worse among athletes with SD after injury compared to injured athletes without SD. Similar performances on concussion assessments for the SRC only and SD only groups suggest SD may appear similar to clinical presentation of concussion, even at baseline in the absence of SRC.

Nonsteroidal anti-inflammatory drug use and concussions in adolescent athletes: incidence, severity, and recovery

OBJECTIVE

Given concerns about the potential long-term effects of concussion in young athletes, concussion prevention has become a major focus for amateur sports leagues. Athletes have been known to frequently use anti-inflammatory medications to manage injuries, expedite return to play, and treat concussion symptoms. However, the effects of baseline nonsteroidal anti-inflammatory drug (NSAID) use on the susceptibility to head injury and concussion remain unclear. This study aims to assess the effects of preinjury NSAID use on concussion incidence, severity, and recovery in young athletes.

METHODS

Data from 25,815 ImPACT (Immediate Post-Concussion Assessment and Cognitive Testing) tests were obtained through a research agreement with ImPACT Applications Inc. Subjects ranged in age from 12 to 22 years old. Those who reported NSAID use at baseline were assigned to one (anti-inflammatory [AI]) cohort, whereas all others were assigned to the control (CT) cohort. Differences in head trauma and concussion incidence, severity, and recovery were assessed using chi-square tests, unpaired t-tests, and Kaplan-Meier plots.

RESULTS

The CT cohort comprised a higher percentage (p < 0.0001) of males (66.30%) than the AI cohort (44.16%) and had a significantly greater portion of athletes who played football (p = 0.004). However, no statistically significant differences were found between the two cohorts in terms of the incidence of head trauma (CT = 0.489, AI = 0.500, p = 0.9219), concussion incidence (CT = 0.175, AI = 0.169, p = 0.7201), injury severity, or median concussion recovery time (CT = 8, AI = 8, p = 0.6416). In a multivariable analysis controlling for baseline differences between the cohorts, no association was found between NSAID use and concussion incidence or severity.

CONCLUSIONS

In this analysis, the authors found no evidence that preinjury use of NSAIDs affects concussion risk in adolescent athletes. They also found no indication that preinjury NSAID use affects the severity of initial injury presentation or concussion recovery.

Preliminary Evidence of a Dose-Response for Continuing to Play on Recovery Time After Concussion

OBJECTIVE

To investigate a dose-response relationship between continuing to play following concussion and outcomes.

PARTICIPANTS

A total of 130 athletes (age 11-19 years).

DESIGN

Repeated-measures design comparing symptoms, neurocognitive performance, and recovery time between 52 athletes immediately removed from play (Removed), 24 who continued to play for 15 minutes or less (Short-Play), and 32 who continued to play for more than 15 minutes (Long-Play).

MAIN MEASURES

Recovery was the number of days from injury to clearance. Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) measured neurocognitive outcomes and the Post-Concussion Symptom Scale (PCSS) measured symptom severity.

RESULTS

Long-Play (44.09 ± 27.01 days) took longer to recover than Short-Play (28.42±12.74 days) and Removed (18.98 ± 13.76 days). Short-Play was 5.43 times more likely, and Long-Play 11.76 times more likely, to experience protracted recovery relative to Removed. Both Play groups had worse neurocognitive performance and higher symptom scores than Removed at days 1 to 7, with Long-Play demonstrating worse reaction time than Short-Play. At days 8 to 30, both Play groups performed worse than Removed on visual memory and visual motor speed, while only Long-Play performed worse on verbal memory and reaction time.

CONCLUSIONS

Results provide initial evidence of a dose-response effect for continuing to play on recovery from concussion, highlighting the importance of removal from play.

Methodological considerations of assessing meaningful/reliable change in computerized neurocognitive testing following sport-related concussion

OBJECTIVE

Traditional reliable change index (RCI) methods may be psychometrically limited due to their inability to account for particularly high or low baseline performance and regression to the mean following serial testing. The current study sought to examine differences between RCI and standardized regression-based (RBz) methods in a cohort of adolescent athletes engaged in sport-related concussion recovery.

METHODS

Consultation records and results of computerized testing data via the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) battery were retrospectively reviewed among 240 adolescent athletes involved in return-to-play protocols following a sport-related concussion.

RESULTS

High concordance rates were found between RCI and RBz metrics across ImPACT composites, consistent with previous literature. However, especially for those with lower baseline performance, RBz scores tended to suggest cognitive performance not meeting or exceeding baseline scores despite RCI metrics being appropriate across speed-based ImPACT composites. In contrast, results revealed high rates of RCI scores suggesting continued cognitive difficulties despite RBz metrics being within normal limits, especially for adolescents with higher baseline performance.

CONCLUSIONS

Results suggest value in interpreting RBz values in addition to RCI values as these allow for clinical interpretation more sensitive to statistical confounds, including baseline performance and regression to the mean.

Sex-Related Differences in the Incidence, Severity, and Recovery of Concussion in Adolescent Student-Athletes Between 2009 and 2019

BACKGROUND

The sex of an athlete is thought to modulate concussion incidence; however, the effects of sex on concussion severity and recovery are less clear.

PURPOSE

To evaluate sex differences in concussion severity and recovery using a large, heterogeneous sample of young student-athletes with the goal of understanding how sex affects concussion outcomes in young athletes.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The Immediate Post-Concussion Assessment and Cognitive Testing results of 11,563 baseline and 5216 postinjury tests were used to calculate the incidence of concussion of adolescent male and female student-athletes ages 12 to 22 years (median, 15 years). The postinjury tests of 3465 male and 1751 female student-athletes evaluated for concussion or head trauma were used to assess differences in the Severity Index (SI) and recovery. Chi-square tests and t tests were used to compare differences in demographic characteristics, incidence, and SI between the 2 cohorts. Multivariable linear, logistic, and Cox proportional hazards regressions were used to control for differences between cohorts in analyses of incidence, SI, and recovery.

RESULTS

When we controlled for demographic differences, female participants had higher odds of concussion (odds ratio, 1.62; 95% CI, 1.40-1.86; P < .0001) and higher SI after concussion (β = 0.67; 95% CI, 0.02-1.32; P = .04). This discrepancy in SI was a result of differences in Symptom (2.40 vs 2.94; P < .0001) and Processing Speed (0.91 vs 1.06; P = .01) composite scores between male and female participants, respectively. We found no effect of sex on time to recovery when controlling for initial concussion SI (hazard ratio, 0.94; 95% CI, 0.78-1.12; P = .48).

CONCLUSION

Using large, multisport cohorts, this study provides evidence that female athletes are at higher risk for more concussions and these concussions are more severe, but male and female athletes have similar recovery times when the analysis controls for initial concussion SI.

Baseline preseason ImPACT® testing in Mandarin with adolescent student-athletes in the United States

Researchers have examined differences on ImPACT^® in baseline symptom reporting and neurocognitive performances based on the language of administration and racial/ethnic identity. This is the first study to examine differences between student-athletes tested in Mandarin versus English on ImPACT^® during preseason baseline assessments conducted in high schools in the United States. Participants included 252 adolescent student-athletes who completed ImPACT^® testing in the state of Maine in Mandarin and 252 participants who completed testing in English, matched on age, gender, and health and academic history. Participants were compared on neurocognitive composite scores and symptom ratings. Boys tested in Mandarin, but not girls, had modestly better neurocognitive performance on one of four composite scores (i.e., Visual Motor Speed, p < .001, d = .45). Although language groups did not differ in total symptom severity, boys tested in Mandarin endorsed multiple physical symptoms at higher rates than boys tested in English. These results suggest that the current ImPACT^® neurocognitive normative data are reasonably appropriate for use with adolescents evaluated in Mandarin. There were some differences in the reporting of physical symptoms, with greater rates of symptom endorsement by boys tested in Mandarin than boys tested in English; but overall symptom severity ratings were comparable between the language groups.

Test-retest reliability of the Turkish translation of the Penn Computerized Neurocognitive Battery

Psychiatric disorders are associated with cognitive dysfunction (CD), and reliable screening and follow-up of CD is essential both for research and clinical practice globally; yet, most assessments are in Western languages. We aimed to evaluate the test-retest reliability of the Turkish version of the Penn Computerized Neurocognitive Battery (PennCNB) to guide confident interpretation of results. Fifty-eight healthy individuals completed the PennCNB Turkish version in two sessions. After quality control, reliability analysis was conducted using Intraclass Correlation Coefficients (ICC), corrected for practice effects. Most measures were not significantly different between the sessions and had acceptable ICC values, with several exceptions. Scores were improved considerably for some memory measures, including immediate Facial Memory and Spatial Memory, and for incorrect responses in abstraction and mental flexibility, with correspondingly acceptable ICCs. Test-retest assessment of the Turkish version of the PennCNB shows that it can be used as a reliable real-time measurement of cognitive function in snapshot cross-sectional or longitudinal determinations. Preliminary validity assessment in this normative sample showed expected positive correlations with education level and negative correlations with age. Thus, the Turkish version of the PennCNB can be considered a reliable neuropsychological testing tool in research and clinical practice. Practice effects should be considered, especially when applied in short intervals. Significantly better performances in the retest, beyond practice effect, likely reflect nonlinear improvements in some participants who "learned how to learn" the memory tests or had insight on solving the abstraction and mental flexibility test.

Comparing Before- and After-School Neurocognitive Performance in High School Athletes: Implications for Concussion Management

OBJECTIVE

To compare before- and after-school neurocognitive performance and total symptoms in a sample of nonconcussed high school athletes.

DESIGN

Repeated-measures, counterbalanced design.

SETTING

Midwest high schools.

PARTICIPANTS

Thirty-nine nonconcussed high school athletes.

INTERVENTIONS

The Immediate Post-Concussion Assessment and Cognitive Testing battery was administered before and after school in a counterbalanced testing order.

MAIN OUTCOME MEASURES

Neurocognitive and total symptom scores.

RESULTS

Paired-sample t tests revealed no significant differences in verbal memory (P = 0.43), visual memory (P = 0.44), processing speed (P = 0.94), reaction time (P = 0.16), or total symptoms (P = 0.52) between before- and after-school testing sessions.

CONCLUSIONS

The results of this study expand on best practice guidelines for baseline and postinjury concussion computerized neurocognitive testing and symptom report administration. This study suggests that sports medicine professionals can administer computerized neurocognitive testing before or after school without concern of confounding factors affecting performance or total symptoms.

A Cohort Study of the Temporal Stability of ImPACT Scores Among NCAA Division I Collegiate Athletes: Clinical Implications of Test-Retest Reliability for Enhancing Student Athlete Safety

OBJECTIVE

In this study we examined the temporal stability of the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) within NCAA Division I athletes across various timepoints using an exhaustive series of statistical models.

METHODS

Within a cohort design, 48 athletes completed repeated baseline ImPACT assessments at various timepoints. Intraclass correlation coefficients (ICC) were calculated using a two-way mixed effects model with absolute agreement.

RESULTS

Four ImPACT composite scores (Verbal Memory, Visual Memory, Visual Motor Speed, and Reaction Time) demonstrated moderate reliability (ICC = 0.51-0.66) across the span of a typical Division I athlete's career, which is below previous reliability recommendations (0.90) for measures used in individual decision-making. No evidence of fixed bias was detected within Verbal Memory, Visual Motor Speed, or Reaction Time composite scores, and minimal detectable change values exceeded the limits of agreement.

CONCLUSIONS

The demonstrated temporal stability of the ImPACT falls below the published recommendations, and as such, fails to provide robust support for the NCAA's recommendation to obtain a single preparticipation cognitive baseline for use in sports-related concussion management throughout an athlete's career. Clinical interpretation guidelines are provided for clinicians who utilize baseline ImPACT scores for later performance comparisons.

How Do ImPACT Quick Test Scores Compare with ImPACT Online Scores in Non-Concussed Adolescent Athletes?

OBJECTIVE

To compare neurocognitive scores between the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) Quick Test (QT) and Online Versions in non-concussed high school athletes.

METHODS

A sample of 47 high school athletes completed the ImPACT Online Version pre-season and the ImPACT QT approximately 3 months later. Paired sample t-tests and Pearson's correlations examined differences and relationships between the ImPACT batteries.

RESULTS

The ImPACT QT scores were significantly higher for performance on the Three Letters: Average Counted (p < .001, d = .88), Three Letters: Average Counted Correctly (p < .001, d = .80), and Symbol Match: Correct RT Visible (p < .001, d = .72), and Symbol Match: Correct RT Hidden (p = .002, d = .50) subtests. There were significant relationships for Three Letters: Average Counted (r = .85, p < .001), Three Letters: Average Counted Correctly (r = .82, p < .001), and Symbol Match: Total Correct Hidden (r = .40, p = .006) subtests.

CONCLUSIONS

Post-injury evaluation data using ImPACT QT should be compared to normative referenced data, and not to pre-season data from the ImPACT Online Version.

Reliability of Objective Eye-Tracking Measures Among Healthy Adolescent Athletes

OBJECTIVE

To determine the test-retest correlation of an objective eye-tracking device among uninjured youth athletes.

DESIGN

Repeated-measures study.

SETTING

Sports-medicine clinic.

PARTICIPANTS

Healthy youth athletes (mean age = 14.6 ± 2.2 years; 39% women) completed a brief, automated, and objective eye-tracking assessment.

INDEPENDENT VARIABLES

Participants completed the eye-tracking assessment at 2 different testing sessions.

MAIN OUTCOME MEASURES

During the assessment, participants watched a 220-second video clip while it moved around a computer monitor in a clockwise direction as an eye tracker recorded eye movements. We obtained 13 eye movement outcome variables and assessed correlations between the assessments made at the 2 time points using Spearman's Rho (rs).

RESULTS

Thirty-one participants completed the eye-tracking evaluation at 2 time points [median = 7 (interquartile range = 6-9) days between tests]. No significant differences in outcomes were found between the 2 testing times. Several eye movement variables demonstrated moderate to moderately high test-retest reliability. Combined eye conjugacy metric (BOX score, rs = 0.529, P = 0.008), the variance of the ratio for both eye movements in the horizontal (rs = 0.497, P = 0.013) and vertical (rs = 0.446; P = 0.029) movement planes along the top/bottom of the computer screen, and the variance of the left and right eye movement along the bottom segment of the computer screen (rs = 0.565; P = 0.004) each demonstrated moderate between-test correlations.

CONCLUSIONS

Automated and quantitative eye movement and conjugacy metrics provide relatively stable measurements among a group of healthy youth athletes. Thus, their inclusion as a visual tracking metric may be complementary to other visual examination techniques when monitoring concussion recovery across time.

Estimated Age of First Exposure to American Football and Neurocognitive Performance Amongst NCAA Male Student-Athletes: A Cohort Study

BACKGROUND

Repetitive head impacts in young athletes are potentially detrimental to later life (e.g., age 50 + years) neurological function; however, it is unknown what the short-term effects (e.g., age 20 years) are in collegiate student-athletes.

OBJECTIVE

The purpose of this study was to determine the effect of the estimated age of first exposure to American tackle football participation on neurocognitive performance and symptom severity scores in collegiate student-athletes.

METHODS

We used a cohort study in which neurocognitive performance was assessed using the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) test in 4376 male athletes (age 19.3 ± 1.5 years, mass 96.3 ± 20.3 kg, height 185.0 ± 7.4 cm). Athletes were grouped by sport participation [American football (n = 3462) or non-contact (n = 914)] and estimated age of first exposure [< 12 years (n = 3022) or ≥ 12 years (n = 1354)]. The outcome measures were the four primary cognitive scores and the symptom severity score from ImPACT. We assessed primary outcomes across groups, controlling for age, learning accommodations, and concussion history.

RESULTS

Neurocognitive performance was not associated with the estimated age of first exposure-by-group interaction.

CONCLUSION

Our findings indicate that participation in American tackle football before age 12 years does not result in neurocognitive deficits in college. Therefore, we suggest the following: the consequences of early exposure to repetitive head impacts do not manifest by college, the ImPACT test was not sensitive enough to identify the effects of an earlier estimated age of first exposure, or there is no association between an earlier estimated age of first exposure and neurocognitive functioning. Future longitudinal studies are warranted.

Concussion Clinical Profiles Screening (CP Screen) Tool: Preliminary Evidence to Inform a Multidisciplinary Approach

BACKGROUND

Current concussion symptom inventories emphasize total number or symptoms and severity and overlap with other conditions, such as mental health disorders, which may limit their specificity and clinical utility.

OBJECTIVE

To develop and test the reliability and validity of a new Concussion Clinical Profiles Screening tool (CP Screen) in both healthy controls and concussed.

METHODS

CP Screen is a 29-item self-report, clinical profile-based symptom inventory that measures the following 5 concussion clinical profiles: 1) anxiety/mood, 2) cognitive/fatigue, 3) migraine, 4) ocular, and 5) vestibular; and the following 2 modifying factors: 1) sleep and 2) neck. Post-Concussion Symptom Scale (PCSS), vestibular/ocular motor screening (VOMS) tool, and Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) were conducted. CP Screen was administered in community a concussion surveillance program and 2 sports medicine concussion clinics. Responses include 248 athletes, 121 concussed, and 127 controls, enrolled between 2018 and 2019.

RESULTS

Internal consistency of the CP Screen in the control (Cronbach's alpha = .87) and concussed (Cronbach's alpha = .93) samples was high. Moderate to high correlations among the CP Screen factors and PCSS factors and VOMS items, supporting concurrent validity. ROC curve analysis for identifying concussed from controls was significant (P &lt; .001) for all CP Screen factor and modifier scores with excellent AUCs for migraine (.93), ocular (.88), vestibular (.85), and cognitive (.81) factors, demonstrating predictive validity.

CONCLUSION

The CP Screen demonstrated strong reliability, concurrent validity with commonly used concussion assessment (ie, PCSS, VOMS, and ImPACT), and predictive validity for identifying concussion. The CP Screen extends current symptom inventories by evaluating more specific symptoms that may reflect clinical profiles and inform better clinical care.

Influence of Test Environment, Age, Sex, and Sport on Baseline Computerized Neurocognitive Test Performance

BACKGROUND

Baseline computerized testing is a common component of concussion assessments, and the testing environment has been suggested to influence test performance and validity.

PURPOSE

To compare concussion baseline computerized neurocognitive test performance and validity among adolescent athletes based on testing environment (group, individual), age group (10-12, 13-15, 16-18 years), sex (male, female), and sport type (collision/combat, contact, noncontact).

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Through a concussion community outreach program, participants completed baseline computerized neurocognitive testing using Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). A total of 2845 athletes aged 10 to 18 years completed the baseline assessment. A total of 2241 (79%) athletes completed baseline testing in a group environment, and 604 (21%) completed testing in an individual environment. A random subsample of 500 athletes from each group was selected for statistical comparison.

RESULTS

No significant differences were supported in baseline computerized neurocognitive test performance between the group and individual administration environments. Test validity was statistically similar across testing environment, age group, and sex. However, patients of older age (16-18 years), female sex, and collision/combat and contact sports performed better on ImPACT. There were differences in total symptom severity scores (t = 2.19, df = 998, P = .03), with participants in the group testing environment reporting lower total symptom severity scores than those in the individual testing environment. The rates of invalid tests were low across all age groups, averaging from 4.0% in the 10- to 12-year age group to 4.8% in the 13- to 15-year age group.

CONCLUSION

The findings indicated that concussion baseline neurocognitive test performance is similar when administered in group and individual testing environments. However, differences based on age group, sex, and sport type should be considered when interpreting baseline computerized neurocognitive test scores. The finding of higher symptom scores in older adolescents in the individual testing environment suggests that they may be less forthcoming about symptoms in a group setting.

Motion Sickness Susceptibility and Baseline Vestibular and Ocular-Motor Performance in Adolescent Athletes

CONTEXT

High school athletes with a history of motion sickness susceptibility exhibit higher baseline vestibular and ocular-motor scores than those without a history of motion sickness susceptibility.

OBJECTIVE

To examine the effects of motion sickness susceptibility on baseline vestibular and ocular-motor functioning, neurocognitive performance, and symptom scores.

DESIGN

Cross-sectional study.

SETTING

Preseason concussion testing.

PATIENTS OR OTHER PARTICIPANTS

A convenience sample of high school athletes (N = 308, age = 15.13 ± 1.21 years) involved in a variety of sports.

MAIN OUTCOME MEASURE(S)

Vestibular/Ocular Motor Screening, computerized neurocognitive assessment, symptom scale, and Motion Sickness Susceptibility Questionnaire-Short Form (MSSQ-S).

RESULTS

Participants were categorized into 3 groups based on a median split of the scores (eg, NONE, LOW, and HIGH). The LOW (n = 95) and HIGH (n = 92) groups (ie, MSSQ-S score > 0) were 2.64 times more likely (χ²_1,257 = 7.94, P = .01, 95% confidence interval = 1.32, 5.26) to have baseline Vestibular/Ocular Motor Screening scores larger than the clinical cutoffs for the NONE group (n = 70). No between-groups main effects were present for the NONE (n = 52), LOW (n = 89), and HIGH (n = 90) MSSQ-S groups for verbal (F_2,230 = .09, P = .91, η² = .001) and visual (F_2,230 = .15, P = .86, η² = .001) memory, processing speed (F_2,230 = .78, P = .46, η² = .007), or reaction time (F_2,230 = 2.21, P = .11, η² = .002). The HIGH group exhibited higher total baseline symptom scores than the LOW (U = 3325.50, z = -1.99, P = .05, r = .15) and NONE (U = 1647.50, z = -2.83, P = .005, r = .24) groups.

CONCLUSIONS

Motion sickness should be considered a preexisting risk factor that might influence specific domains of the baseline concussion assessment and postinjury management.

Family History of Migraine Associated With Posttraumatic Migraine Symptoms Following Sport-Related Concussion

OBJECTIVE

To determine whether family history of migraine increased the likelihood of posttraumatic migraine (PTM) symptom presentation in adolescents following concussion, and examine the influence of family history of migraine and PTM on postinjury outcomes.

SETTING

Outpatient concussion clinic.

PARTICIPANTS

A total of 153 patients with concussion (103 males and 50 females) aged 15.72 ± 1.48 years (range 12-18 years).

DESIGN

Cross-sectional, observational study of patients presenting for initial evaluation 4.72 ± 3.05 days (range 1-14) postinjury.

MAIN MEASURES

Computerized neurocognitive testing, symptom report, and vestibular/oculomotor screening.

RESULTS

Patients with a family history of migraine were 2.6 times (odds ratio = 2.60, confidence interval = 1.35-5.02, P = .003) more likely to present with PTM compared with patients without a family history. Results of multivariate analyses of covariance, controlling for concussion history, revealed significant main effects for PTM on (1) Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT)/Post-Concussion Symptom Scale (PCSS) (F = 15.43, P <.001) and (2) Vestibular/Ocular Motor Screening (VOMS) (F = 8.52, P < .001). There was no main effect for family history of migraine on ImPACT/PCSS (P = .22) and VOMS (P = .83) or interaction between family history of migraine and PTM on ImPACT/PCSS (P = .84) and VOMS (P = .52).

CONCLUSION

Family history of migraine is associated with PTM symptoms following sport-related concussion, suggesting a genetic predisposition for migraine may serve as a catalyst or trigger for onset of PTM. However, only presence of PTM, rather than family history of migraine, was related to worse neurocognitive and vestibular/oculomotor outcomes.

History of High Motion Sickness Susceptibility Predicts Vestibular Dysfunction Following Sport/Recreation-Related Concussion

OBJECTIVE

To compare vestibular dysfunction at 1 to 10 and 11 to 20 days following sport/recreation-related concussion (SRC) in athletes with and without history of motion sickness susceptibility. Secondary aims of this study were to investigate differences in neurocognitive performance and affective symptoms in these groups.

DESIGN

Cross-sectional.

SETTING

Concussion Specialty Clinic.

PARTICIPANTS

One hundred twenty-four adolescents and adults (82 males, 42 females) aged 14 to 26 (16.36 ± 2.10) years, diagnosed with SRC in the past 10 (4.56 ± 2.54) days; 47 participants composed the sample for quartile analyses.

INDEPENDENT VARIABLE

Motion sickness susceptibility questionnaire short form score.

MAIN OUTCOME MEASURES

Computerized neurocognitive test scores, vestibular/oculomotor screening scores (VOMS), and symptom factor scores from a standardized concussion symptom inventory.

RESULTS

There was no association between history of motion sickness susceptibility and VOMS scores (above or below clinical cutoff) at 1 to 10 days after injury, although at 11 to 20 days after injury there was an association between high motion sickness susceptibility and symptoms above clinical cutoff on 5 of the 6 VOMS items (P values 0.01-0.04). The high motion sickness group had more affective symptoms on the symptom inventory than the no motion sickness group (P = 0.002) at 1 to 10 days after injury. Groups did not differ on computerized neurocognitive testing (P = 0.11).

CONCLUSION

Athletes with a preexisting history of motion sensitivity may exhibit more prolonged vestibular dysfunction following SRC, and may experience more affective symptoms early in recovery.

Self-reported head injury symptoms exacerbated in those with previous concussions following an acute bout of purposeful soccer heading

Rates of concussion in soccer are high, especially in female players. The primary aim of this study was to examine differences in self-reported concussion-related symptoms (CRS), balance (BESS), and neurocognitive performance (ImPACT) following an acute bout of soccer heading in a group of female collegiate players with and without a history of concussion. Eighty-seven players with 0 to 3+ previous concussions participated. The measurement variables were assessed before and after heading sessions; including one linear and one rotational bout. Players with concussion histories reported more CRS than their non-concussed teammates both before and after the heading sessions. Balance and neurocognitive scores were generally unaffected. This finding should heighten our awareness to carefully monitor soccer players who have experienced concussions and be aware that they may develop concussion-like symptoms, especially after acute bouts of heading either during practice or in matches. The long-term implications of this finding remain unknown.

Descriptive Analysis of a Baseline Concussion Battery Among U.S. Service Academy Members: Results from the Concussion Assessment, Research, and Education (CARE) Consortium

Introduction

The prevalence and possible long-term consequences of concussion remain an increasing concern to the U.S. military, particularly as it pertains to maintaining a medically ready force. Baseline testing is being used both in the civilian and military domains to assess concussion injury and recovery. Accurate interpretation of these baseline assessments requires one to consider other influencing factors not related to concussion. To date, there is limited understanding, especially within the military, of what factors influence normative test performance. Given the significant physical and mental demands placed on service academy members (SAM), and their relatively high risk for concussion, it is important to describe demographics and normative profile of SAMs. Furthermore, the absence of available baseline normative data on female and non-varsity SAMs makes interpretation of post-injury assessments challenging. Understanding how individuals perform at baseline, given their unique individual characteristics (e.g., concussion history, sex, competition level), will inform post-concussion assessment and management. Thus, the primary aim of this manuscript is to characterize the SAM population and determine normative values on a concussion baseline testing battery.

Materials and Methods

All data were collected as part of the Concussion Assessment, Research and Education (CARE) Consortium. The baseline test battery included a post-concussion symptom checklist (Sport Concussion Assessment Tool (SCAT), psychological health screening inventory (Brief Symptom Inventory (BSI-18) and neurocognitive evaluation (ImPACT), Balance Error Scoring System (BESS), and Standardized Assessment of Concussion (SAC). Linear regression models were used to examine differences across sexes, competition levels, and varsity contact levels while controlling for academy, freshman status, race, and previous concussion. Zero inflated negative binomial models estimated symptom scores due to the high frequency of zero scores.

Results

Significant, but small, sex effects were observed on the ImPACT visual memory task. While, females performed worse than males (p < 0.0001, pη2 = 0.01), these differences were small and not larger than the effects of the covariates. A similar pattern was observed for competition level on the SAC. There was a small, but significant difference across competition level. SAMs participating in varsity athletics did significantly worse on the SAC compared to SAMs participating in club or intramural athletics (all p's < 0.001, η2 = 0.01). When examining symptom reporting, males were more than two times as likely to report zero symptoms on the SCAT or BSI-18. Intramural SAMs had the highest number of symptoms and severity compared to varsity SAMs (p < 0.0001, Cohen's d < 0.2). Contact level was not associated with SCAT or BSI-18 symptoms among varsity SAMs. Notably, the significant differences across competition level on SCAT and BSI-18 were sub-clinical and had small effect sizes.

Conclusion

The current analyses provide the first baseline concussion battery normative data among SAMs. While statistically significant differences may be observed on baseline tests, the effect sizes for competition and contact levels are very small, indicating that differences are likely not clinically meaningful at baseline. Identifying baseline differences and significant covariates is important for future concussion-related analyses to inform concussion evaluations for all athlete levels.

The Montreal Cognitive Assessment as a Cognitive Screening Tool in Athletes

Background: The Montreal Cognitive Assessment (MoCA) is a cognitive screening tool known to accurately measure mild cognitive impairment (MCI) in many different neurological populations. Objective: We aimed to determine whether a sport-related concussion (SRC) history and other concussion modifiers influence global cognitive function in high-performance athletes. Methods: A cross-sectional study of 326 varsity and national team athletes aged 18–36 years was completed at the University of Calgary Sports Medicine Clinic, Calgary, Alberta, Canada. Logistic regression analysis was used to examine the association between the total MoCA score, MoCA subscales, and number of previous SRC, adjusting for age, sex, sport participation (SP), and concussion modifiers. Results: Athletes with a history of three or more SRC were 5.36 times more likely to score less than 26/30 on the MoCA (the cutoff for MCI) compared to athletes with two or less SRC (p = 0.02). Males were 2.23 times more likely to have MCI than females (p = 0.0004). There was a significant relationship between the number of previous concussions and the MoCA subscales of attention (p = 0.05) and abstraction (p = 0.003). Age, SP, and concussion modifiers (migraine, depression, anxiety, and attention deficit and hyperactivity disorder) did not influence the relationship between MoCA and previous concussion history. Conclusion: In the appropriate clinical context, cognitive screening with the MoCA may benefit clinical care in athletes with multiple previous SRC, but should not replace a full neuropsychological assessment. Thus, further research is needed to compare the MoCA to full neuropsychological assessments in this population.

A systematic review of sex differences in concussion outcome: What do we know?

Objective: The purpose of this review was to examine sex differences in concussion, or mild traumatic brain injury (mTBI) outcome, updating previous critical reviews of the literature. Method: Within adult human studies, we reviewed a wide range of concussion outcome variables: prevalence of concussion, injury characteristics, postconcussion symptom trajectories and psychiatric distress, neuropsychological performance, and neuroimaging findings. Sports-related concussion, civilian, and military samples were included in the review. Results: Given the robust concussion literature, there is a relative paucity of research addressing sex differences following concussion. The majority of available studies focused on sports-related concussion, with fewer studies targeting other civilian causes of concussion or military-related concussion in females. Prevalence of concussion was generally reported to be higher in females than males. Although symptom reporting largely showed a pattern for females to report greater overall symptoms than males, examining individual symptoms or symptom clusters resulted in mixed findings between the sexes. Neuropsychological studies generally showed females performing more poorly than males on measures of visual memory following concussion, though this finding was not consistently reported. Conclusion: Research examining sex differences in humans following concussion, in general, is in its infancy, and exploration of sex differences in studies outside of the sports concussion domain is particularly nascent. Given the increased prevalence of concussion and potential higher symptom reporting among women, ongoing research is necessary to better understand the role of biological sex on outcome following concussion. Understanding sex differences has important implications for assessment, management, and treatment of concussion.

Test Performance and Test-Retest Reliability of the Vestibular/Ocular Motor Screening and King-Devick Test in Adolescent Athletes During a Competitive Sport Season

BACKGROUND

The Vestibular/Ocular Motor Screening (VOMS) and King-Devick (K-D) test are tools designed to assess ocular or vestibular function after a sport-related concussion.

PURPOSE

To determine the test-retest reliability and rate of false-positive results of the VOMS and K-D test in a healthy athlete sample.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

Forty-five healthy high school student-athletes (mean age, 16.11 ± 1.43 years) completed self-reported demographics and medical history and were administered the VOMS and K-D test during rest on day 1 (baseline). The VOMS and K-D test were administered again once during rest (prepractice) and once within 5 minutes of removal from sport practice on day 2 (removal). The Borg rating of perceived exertion scale was administered at removal. Intraclass correlation coefficients were used to determine test-retest reliability on the K-D test and the average near point of convergence (NPC) distance on the VOMS. Level of agreement was used to examine VOMS symptom provocation over the 3 administration times. Multivariate base rates were used to determine the rate of false-positive results when simultaneously considering multiple clinical cutoffs.

RESULTS

Test-retest reliability of total time on the K-D test (0.91 [95% CI, 0.86-0.95]) and NPC distance (0.91 [95% CI, 0.85-0.95]) was high across the 3 administration times. Level of agreement ranged from 48.9% to 88.9% across all 3 times for the VOMS items. Using established clinical cutoffs, false-positive results occurred in 2% of the sample using the VOMS at removal and 36% using the K-D test.

CONCLUSION

The VOMS displayed a false-positive rate of 2% in this high school student-athlete cohort. The K-D test's false-positive rate was 36% while maintaining a high level of test-retest reliability (0.91). Results from this study support future investigation of VOMS administration in an acutely injured high school athletic sample. Going forward, the VOMS may be more stable than other neurological and symptom report screening measures and less vulnerable to false-positive results than the K-D test.

Sandbagging on the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) in a high school athlete population

The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is a computerized neuropsychological test battery commonly used to assess cognitive functioning after a concussion. It is recommended that application of ImPACT utilizes a baseline administration so athletes have an individualized baseline with which to compare post-injury results should they sustain a concussion. It has been suggested that athletes may provide suboptimal effort, called "sandbagging," in order to return to their baseline cognitive scores, and thus to play, more quickly. This research examines ImPACT baseline scores when high school athletes were asked to attempt to "sandbag," and compares those scores with scores obtained when they were asked to give their "best effort." Fifty-four high school student athlete volunteers participated in the study. In contrast to previous research that just looked at the cut-score invalidity indicators built into ImPACT, this research developed a regression equation to predict sandbagging. A logistic regression equation developed with four variables that demonstrated the largest effect size between "best effort" and "sandbagged" baselines showed a 99.7% classification accuracy for the "best effort" and "sandbag" groups.

An Examination of Adolescent Athletes and Nonathletes on Baseline Neuropsychological Test Scores

CONTEXT

  An estimated 15.3 million adolescent students are enrolled in US high schools, with approximately 7.8 million participating in athletics. Researchers have examined various demographics in high school athletes; however, athletic participation may play a larger role in test performance than previously thought. Currently, investigations of concussion assessment may rely on uninjured athletes as controls. However, due to the intense nature of athletics, this may not be an appropriate practice.

OBJECTIVE

  To examine differences between athletes and nonathletes using a common computerized neuropsychological test.

DESIGN

  Retrospective cross-sectional study.

SETTING

  High schools from a school district in Columbus, Ohio.

PATIENTS OR OTHER PARTICIPANTS

  A total of 662 adolescent high school students (athletes: n = 383, female n = 18; nonathletes: n = 279, female n = 193).

MAIN OUTCOME MEASURE(S)

  Participants were administered a computerized neuropsychological test battery (Immediate Post-Concussion Assessment and Cognitive Test [ImPACT]) during baseline concussion assessment. Differences between groups were established for output composite scores.

RESULTS

  Differences were found between athletes and nonathletes in composite reaction time ( F_1,522 = 14.855, P < .001) and total symptom score ( F_1,427 = 33.770, P < .001). Nonathletes reported more symptoms, whereas athletes had faster reaction times. No differences were present in composite verbal memory, composite visual memory, composite visual motor speed, or composite impulse control ( P > .05).

CONCLUSIONS

  Symptom reporting and reaction time differed between high school athletes and nonathletes. Participation in extracurricular activities may lead to cognitive differences in adolescents that can influence performance on the Immediate Post-Concussion Assessment and Cognitive Test battery. Researchers should account for these differences in baseline performance when making concussion diagnostic and management decisions.

Valid but Invalid: Suboptimal ImPACT Baseline Performance in University Athletes

PURPOSE

This study aimed to investigate the frequency of valid yet suboptimal Immediate Postconcussion Assessment and Cognitive Test (ImPACT) performance in university athletes and to explore the benefit of subsequent ImPACT administrations.

METHODS

This descriptive laboratory study involved baseline administration of ImPACT to 769 university athletes per the institution's concussion management protocol. Testing was proctored in groups of ≤2 participants. Participants who scored below the 16th percentile according to ImPACT normative data were readministered the ImPACT test up to two additional times because these scores were thought to be potentially indicative of suboptimal effort or poor understanding of instructions. Descriptive analyses were used to examine validity indicators and individual Verbal and Visual Memory, Visual Motor Speed, and Reaction Time ImPACT composite scores in initial and subsequent administrations.

RESULTS

On the basis of ImPACT's validity criteria, 1% (9/769) of administrations were invalid and 14.6% (112/769) had one or more composite score of <16th percentile but were considered valid. After one readministration, 71.4% (80/112) achieved scores of ≥16th percentile and an additional 18 of 32 scored ≥16th percentile after a third administration. Verbal Memory was most commonly <16th percentile on the first administration (43%), Verbal Memory and Visual Motor Speed on the second administration (44% each), and Visual Motor Speed alone on the third administration (50%).

CONCLUSIONS

Approximately 16% of ImPACT records were flagged as invalid or had one or more composite scores of <16th percentile, potentially indicative of suboptimal performance. Upon readministration, 88% of those participants scored >16th percentile. Clinicians must be aware of suboptimal ImPACT performance as it limits the clinical utility of the baseline assessment. Further research is needed to address factors leading to "valid" but invalid baseline performance.

Response Time Reduction Due to Retesting in Mental Speed Tests: A Meta-Analysis

As retest effects in cognitive ability tests have been investigated by various primary and meta-analytic studies, most studies from this area focus on score gains as a result of retesting. To the best of our knowledge, no meta-analytic study has been reported that provides sizable estimates of response time (RT) reductions due to retesting. This multilevel meta-analysis focuses on mental speed tasks, for which outcome measures often consist of RTs. The size of RT reduction due to retesting in mental speed tasks for up to four test administrations was analyzed based on 36 studies including 49 samples and 212 outcomes for a total sample size of 21,810. Significant RT reductions were found, which increased with the number of test administrations, without reaching a plateau. Larger RT reductions were observed in more complex mental speed tasks compared to simple ones, whereas age and test-retest interval mostly did not moderate the size of the effect. Although a high heterogeneity of effects exists, retest effects were shown to occur for mental speed tasks regarding RT outcomes and should thus be more thoroughly accounted for in applied and research settings.

Assessment of Sleep Quantity and Sleep Disturbances During Recovery From Sports-Related Concussion in Youth Athletes

OBJECTIVE

To determine the relation between sleep quantity and sleep disturbances on symptoms and neurocognitive ability during the acute phase (<7d) and after sports-related concussion (SRC; >21d).

DESIGN

Prospective inception cohort study.

SETTING

General community setting of regional middle and high schools.

PARTICIPANTS

A sample (N=971) including youth athletes with SRC (n=528) and controls (n=443) (age, 10-18y).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Athletes completed the Immediate Post-Concussion Assessment and Cognitive Testing battery. Partial correlation analyses and independent t tests were conducted to assess sleep quantity the night before testing. Multivariate analysis of covariance was used to assess sleep disturbances and their interaction with age.

RESULTS

Less sleep quantity was correlated with greater report of cognitive (P=.001) and neuropsychological (P=.024) symptoms specific to prolonged recovery from SRC. Sleep disturbances significantly affect each migraine, cognitive, and neuropsychological symptoms (P<.001). A significant interaction was found between sleep disturbances and age (P=.04) at >21 days post-SRC.

CONCLUSIONS

Findings emphasize that the continued presence of low sleep quantity and sleep disturbances in youth athletes with SRC should be a specific indicator to health professionals that these athletes are at an increased risk of protracted recovery. Further research should identify additional factors that may interact with sleep to increase the risk of protracted recovery.

Comparison of baseline ImPACT performance in amateur motocross riders to football and basketball athletes

PRIMARY OBJECTIVE

The American Motorcyclist Association requires professional riders to undergo baseline computerized neurocognitive testing (CNT) using the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) test for concussion management. It is recommended this practice be expanded to the amateur level, but limited research has explored whether baseline testing is necessary for youth when normative data is available. This study evaluates the utility of baseline testing for amateur riders by comparing their performance to those of traditional youth sports comprising normative datasets.

DESIGN/METHODS

An cross-sectional study comparing amateur motocross (N = 100) riders matched by age and sex to football (N = 100) and basketball (N = 100) athletes performance on baseline ImPACT testing.

RESULTS

ANCOVAs revealed a significant medium effect of group on measures of visual motor speed (F = 11.25, p < 0.001) and reaction time (F = 13.61, p < 0.001). Post hoc analyses revealed that motocross riders were significantly slower compared to football and basketball athletes. There were no significant differences (p > .05) between sport on measures of memory or symptoms.

CONCLUSIONS

Youth motocross riders performed significantly slower on speed measures compared to football and basketball athletes, providing preliminary support for the expansion of baseline ImPACT testing to the amateur level.

Assessing the effects of concussion using the C3Logix Test Battery: An exploratory study

The C3Logix is a computerized concussion assessment tool that measures a wider array of symptoms (i.e., balance and oculomotor functioning) than other computerized batteries. Although the C3Logix has been used increasingly by athletic organizations at all levels of play, its utility within the concussion population has not been extensively examined. The current study aimed to determine whether the C3Logix is sensitive to the effects of concussion. A total of 54 student-athletes enrolled at a large southern university completed the C3Logix at baseline and within days following a suspected concussion (mean = 2.93, SD = 3.14). Dependent-samples t-tests revealed that relative to their baselines, following concussion, athletes both reported significantly greater postconcussive symptoms and performed more poorly on measures of reaction time and computer-measured balance. Decrements in processing speed, visual acuity, and clinician-observed errors on tests of balance also trended toward significance. Results suggest that inclusion of measures of balance and oculomotor functioning in the assessment of concussion may provide additional clinical utility above and beyond domains typically measured by computerized concussion assessments.

A Novel EEG Based Spectral Analysis of Persistent Brain Function Alteration in Athletes with Concussion History

The neurocognitive sequelae of a sport-related concussion and its management are poorly defined. Detecting deficits are vital in making a decision about the treatment plan as it can persist one year or more following a brain injury. The reliability of traditional cognitive assessment tools is debatable, and thus attention has turned to assessments based on electroencephalogram (EEG) to evaluate subtle post-concussive alterations. In this study, we calculated neurocognitive deficits combining EEG analysis with three standard post-concussive assessment tools. Data were collected for all testing modalities from 21 adolescent athletes (seven concussive and fourteen healthy) in three different trials. For EEG assessment, along with linear frequency-based features, we introduced a set of time-frequency (Hjorth Parameters) and nonlinear features (approximate entropy and Hurst exponent) for the first time to explore post-concussive deficits. Besides traditional frequency-band analysis, we also presented a new individual frequency-based approach for EEG assessment. While EEG analysis exhibited significant discrepancies between the groups, none of the cognitive assessment resulted in significant deficits. Therefore, the evidence from the study highlights that our proposed EEG analysis and markers are more efficient at deciphering post-concussion residual neurocognitive deficits and thus has a potential clinical utility of proper concussion assessment and management.

Comparison of Neurocognitive Performance in Contact and Noncontact Nonconcussed High School Athletes Across a Two-Year Interval

Investigating short-term effects of subconcussive impacts on neurocognitive functioning, we employed a repeated measures multivariate model and regression-based measure to examine neurocognitive changes in 771 contact and noncontact high school athletes over a two-year period. Results reveal significant changes in Visual Motor Speed for both groups over a two-year period, with small effect sizes. According to regression-based measures, differences in contact sport athletes' expected Time 2 performances were significant for Visual Motor Speed, also with minimal effects. Results do not conclusively implicate subconcussive hits as the offending factor in differences observed, with gender and sport-type possibly contributing to the small effects.