Progesterone Levels in Adolescent Female Athletes May Contribute to Decreased Cognitive Performance During Acute Phase of Sports-Related Concussion

Although many outcome studies pertaining to sports-related concussion exist, female athletes with concussion remain an understudied group. We examined whether neurocognitive performance in adolescent females with sports-related concussion (SRC) is related to menstrual cycle-related hormone levels measured at one-week post-concussion, one-month post-concussion, or both. Thirty-eight female athletes, ages 14-18, were matched into two groups: SRC or healthy control. Self-reported symptom scores were higher among concussed females in the luteal phase, when progesterone levels are highest. Results suggest that progesterone levels may contribute to a heightened experience of symptoms during the acute phase of SRC, providing further evidence of a possible link between progesterone and symptom scores following concussion.

Sports Neuropsychologists' Ratings of Clinical Criteria Used to Help Determine Concussion Recovery: A Brief Survey Report

OBJECTIVE

To identify criteria used by sports neuropsychologists in determining recovery following sport-related concussion.

METHODS

Forty-six sports neuropsychologists completed a custom survey, rating the importance of specific criteria for determining concussion recovery in youth versus adults. Percentages and modal ratings were documented.

RESULTS

"Back to work/school without accommodations," "No headache after neurocognitive testing," "Feeling 100% back to normal," and "No symptoms after noncontact exertion" were rated highest for youth and adults. "Physician examination without concerns" and "Balance testing" were the two lowest rated items for both youth and adults. For youth, "sufficient" amount of time symptom-free needed for recovery was seen as longer than for adults.

CONCLUSIONS

There was some similarity in how sports neuropsychologists determine concussion recovery for both adults and youth. Future studies should include a larger sample size and concussion experts from other specialties to identify the current multidisciplinary standard of care.

Neurocognitive Concussion Test Performance for Student Athletes on the Autism Spectrum

OBJECTIVE

To examine baseline neurocognitive functioning among adolescent athletes on the autism spectrum based on self-reported level of academic performance.

METHOD

Participants in this cross-sectional, observational study were 6,441 adolescent athletes with a self-reported diagnosis of autism who completed pre-season neurocognitive testing using Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT); 4,742 reported a co-occurring learning disorder (LD), and 6,612 individuals without autism or LD were included as a control group. The majority (57%) self-reported Average Academic Performance, 39% Above Average, and 4% Below Average performance.

RESULTS

Athletes with self-reported autism (with or without LD; 12.2%) were 2.74x (95% CI: 2.17-2.82) more likely to fall below cutoffs for ImPACT Embedded Invalidity Indicators (EVIs), with a significant interaction between self-reported Diagnosis and Academic Performance; individuals with co-occurring autism and LD who reported Below Average Academic Performance had the greatest likelihood of scoring below cutoffs (22%), followed by ASD without LD (14.8%) and Controls (14.6%) with Below Average Academic Performance. Analyses of variance (ANOVAs) revealed main effects of Diagnosis and Academic Performance on neurocognitive performance, with interactions on all ImPACT Composite Scores except Processing Speed.

CONCLUSION

Athletes with self-reported ASD are more likely to fall below ImPACT EVIs and score worse on ImPACT, with greater likelihood/worse performance related to level of academic functioning. Academic performance should be considered when interpreting neurocognitive testing data, to best index neuropsychological functioning associated with concussion in this population. The current findings highlight the importance of individual participant baseline neuropsychological testing for individuals on the autism spectrum.

Reliable Change Indices for the Serial Administration of the Concussion Clinical Profiles Screening Tool

CONTEXT

The Concussion Clinical Profile Screening Tool (CP Screen) self-report concussion symptom inventory that is often administered at weekly intervals. However, 1-week reliable change indices (RCI) for clinical cutoffs and the test-retest reliability of the CP Screen is unknown.

OBJECTIVE

Document RCI cutoff scores and 1-week test-retest reliability for each profile and modifier of the CP Screen for males and females.

DESIGN

Case Series.

SETTING

A large US university.

PATIENTS OR OTHER PARTICIPANTS

173 healthy college students.

MAIN OUTCOME MEASURE(S)

Participants completed two administrations of the CP Screen 7 days apart; CP Screen items yield five clinical profiles and two modifiers. Spearman rho coefficients (rs), intraclass correlation coefficients (ICCs) single measures and Unbiased Estimates of Reliability (UER) were used to assess test-retest reliability. Wilcoxon signed-rank tests assessed differences across time. RCI values and cutoff scores are provided at 90%/95% confidence intervals (CI). All analyses were performed for the total sample and separately for males and females.

RESULTS

RCI cutoffs for clinically significant change (increase/decrease) at a 90% CI for males were as follows: Ocular, Vestibular >2/>4, Anxiety/Mood, Cognitive/Fatigue, Migraine>3/>3, Sleep >4/>6, and Neck>2/>2. RCI cutoffs for clinically significant change (increase/decrease) at a 90% CI for females were as follows: Anxiety/Mood≥2/≥4; Cognitive/Fatigue, Migraine, Ocular, Vestibular, Sleep≥3/≥3; and Neck≥1/≥1. Correlations for CP ranged from .51 (Migraine) to .79 (Anxiety/Mood) for the total sample, .48 (Migraine) to .84 (Vestibular) for males, and .51 (Migraine) to .77 (Ocular) for females. Test-retest indices for each profile and modifier were moderate to good for the total sample (ICC: .64-.82; UER: .79-.90), males (ICC: .60-.87; UER: .76-.94), and females (ICC: .64-.80; UER: .78-.89).

CONCLUSION

The CP Screen is reliable and stable across a 1-week interval, and established RCIs for males and females can help identify meaningful change throughout recovery.

The prevalence and correlates of scores falling below ImPACT embedded validity indicators among adolescent student athletes

Objective: Valid performance on preseason baseline neurocognitive testing is essential for accurate comparison between preseason and post-concussion test results. Immediate Post-Concussion and Cognitive Testing (ImPACT) is commonly used to measure baseline neurocognitive function in athletes. We examined the prevalence of invalid performance on ImPACT baseline testing and identified correlates of invalid performance. Method: The sample included 66,998 adolescents (ages 14-18, M = 15.51 years, SD = 1.22) who completed ImPACT baseline tests between 2009 and 2019. Invalid performance was determined by the embedded validity indicators (EVI). Associations between invalid performance, demographic characteristics, and health conditions were assessed using chi-square tests and odds ratios (ORs). Results: Overall, 7.2% of adolescents had baseline tests identified as invalid by one or more of the EVIs. Individual validity indicators classified between 0.5% and 3.7% tests as invalid. Higher frequencies of invalid scores were observed among youth with neurodevelopmental, academic, and medical conditions. Youth who reported having learning disabilities (n = 3126), receiving special education (n = 3563), or problems with attention-deficit/hyperactivity disorder (ADHD; n = 5104) obtained invalid baselines at frequencies of 16.4%, 16.0%, and 11.1%, respectively. Moreover, youth who reported receiving treatment for a substance use disorder (n = 311) or epilepsy (n = 718) obtained invalid baselines at frequencies of 17.0% and 11.1%, respectively. Conclusions: The base rate of invalid performance on ImPACT's EVIs was approximately 7%, consistent with prior research. Adolescents self-reporting neurodevelopmental conditions, academic difficulties, or a history of treatment for medical conditions obtained invalid baseline tests at higher frequencies. More research is needed to better understand invalid scores in youth with pre-existing conditions.

Understanding racial differences in computerized neurocognitive test performance and symptom-reporting to deliver culturally competent patient-centered care for sport-related concussion

OBJECTIVE

This study examined neurocognitive performance and symptoms between concussed Black and White collegiate athletes at baseline, post-injury, and change from baseline to post-injury.

METHOD

The Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) was used to measure neurocognitive performance and four concussion symptom clusters for 235 concussed collegiate athletes. Between-groups differences were documented at baseline and post-injury, along with change in scores for sex/race, and sport/race groups, using ANOVAs. Baseline scores, and days-to-post-test were covariates in post-injury comparisons. Symptom endorsement by race was evaluated using chi-square analyses.

RESULTS

At baseline, group comparisons by race and sex showed that Black male/female athletes scored lower on reaction time (RT; p = .008), White females scored higher on verbal memory (VerbMem; p = .001), Black females scored lower on visual motor processing speed (VMS; p = .001), and Black football athletes scored slower/poorer on RT (p = .001) and VMS (p = .006). Post-injury, Black males scored lower on visual memory (VisMem; p = .005) and VMS (p = .002), and Black football athletes scored slower on VMS (p = .005), whereas White non-football athletes scored higher on VerbMem (p = .002) and reported fewer symptoms. Significant time-by-sport/race interactions were found for VerbMem (p < .001), VisMem (p < .001) and reported symptoms. With respect to post-injury symptom scores/endorsement, Black athletes scored significantly higher for physical (p = .01) and sleep (p = .01) symptoms.

CONCLUSION

These findings drive the conversation of how subjective measures of symptoms, and objective clinical concussion measures, may relate to the concussion recovery process and providing a culturally competent clinical management approach for diverse patients.

Information seeking behaviors and attitudes of wives of former football players regarding chronic traumatic encephalopathy

This study examines CTE-related knowledge and information-seeking behaviors of caregivers of persons who are at high risk of CTE. Online survey responses were collected from 64 females, ages 18-74, who were married to former college, semiprofessional, or professional football players and were fluent in English. Ranging from 0 to 18, a score was calculated to represent level of CTE knowledge. Participants were classified into groups based on their spouse's reported symptoms and diagnosis. Approximately 87% of participants reported that their spouses have been diagnosed with a football-related concussion and were significantly more likely to seek out information from a healthcare provider, a scientific journal or article, and post/comment on social media compared to spouses of symptomatic/undiagnosed and non-symptomatic groups. Participants reported 77% of available information as probably true, with social media thought to be highly credible. Highest levels of dissatisfaction were reported for league-sponsored websites and physicians/healthcare providers. Although the majority of participants sought CTE related information on regular or social media, and the internet, information sources differed amongst the groups. These findings may help healthcare providers and organizations develop more effective health-related educational programs that will help the wives make informed decisions regarding care for their spouses with respect to CTE.

A-41 Establishing Empirically-Based Normative Cut-Offs For Identifying Anxiety Following Sports-Related Concussion

Purpose: The State–Trait Anxiety Inventory (form Y-1; STAI) is widely used for identifying anxiety in non-clinical and clinical samples. Cutoff scores ≥40 are widely used to identify clinically significant anxiety. However, these scores correspond with the 50th–60th percentile in STAI normative tables. Given that anxiety is recognized as a common post-concussion symptom, and as a post-injury clinical profile, establishing statistically appropriate cutoffs for clinical anxiety is warranted. Methods: We compared rates of individuals falling above static (≥40) versus empirically-derived (&gt;1, &gt;1.5, &gt;2 standard deviations) cutoffs, using a sample of 137 acutely concussed high school and college athletes (59% male, mean age 16.11 ± 1.56 years) who completed the STAI within 7 days of injury (mean 3.79 ± 1.4 days). Results: Approximately 47% of concussed athletes fell above the static cutoff of ≥40, whereas use of empirically-derived cutoffs identified 18% (1SD), 8% (1.5SD) and 3% (2SD). These empirically-derived cutoffs reflect the normal curve, and distribution of scores expected to fall outside 1, 1.5, and 2SD. Conclusions: Use of a static cutoff of ≥40 on the STAI identifies approximately 50% of high school and college athletes as anxious. As such, use of empirically-derived cutoffs are recommended over static cutoffs for clinical anxiety when using the STAI.

A-26 The Prevalence of Invalid Baseline ImPACT® Test Scores in Adolescent Student Athletes

Purpose: Immediate Post-Concussion and Cognitive Testing (ImPACT®) is among the most commonly used neuropsychological measures to establish a baseline estimate of neuropsychological functioning for concussion management. We sought to identify correlates of invalid performance on ImPACT® baseline testing in adolescents. Methods: The sample included 67,009 English-speaking adolescents (ages 14–18, mean: 15.51, SD: 1.22) who completed ImPACT® baseline tests in English between 2009 and 2019. The association between invalid performance (as determined by the embedded invalidity indicators) and demographic and health variables was assessed using chi-square tests and with odds ratios (OR). Results: Overall, 7.2% of adolescents produced invalid baseline tests. Boys (7.9%) produced more invalid baselines than girls (6.2%; χ2 = 70.35, p &lt; 0.001, OR = 1.29, 95% CI = 1.22, 1.37). Adolescents with learning disabilities (16.4%), attention-deficit/hyperactivity disorder (11.1%), and those who have received special education services (16.0%) or repeated more than 1 year of school (11.0%), all obtained invalid baselines at higher frequencies than those who did not endorse these variables (i.e., 6.5%–6.8%; p &lt; 0.001). Adolescents who reported receiving treatment for headaches (9.5%), migraines (9.4%), epilepsy/seizures (11.1%), substance/alcohol use (17.0%), or a psychiatric condition (10.0%) obtained invalid baselines at higher frequencies than those who did not (i.e., 6.6%–6.9%; p &lt; 0.001). Conclusions: Consistent with prior research, approximately 7% of adolescents produced invalid baselines. However, the frequencies of invalid performances were substantially greater for subgroups such as those with learning disabilities, those who have received special education services, and youth who have received past substance abuse treatment.

Norm-Based Cutoffs as Predictors of Prolonged Recovery After Adolescent Sport-Related Concussion

OBJECTIVES

To identify predictors of prolonged recovery (ie, >28 days) using patient demographic factors and healthy, norm-based cutoffs on a multimodal test battery in adolescents after sport-related concussions (SRCs).

DESIGN

Retrospective cohort. Patients were deemed recovered after successful completion of return-to-play/school protocols and received medical clearance.

SETTING

Community concussion clinic.

PATIENTS

Male and female adolescent student athletes diagnosed with a SRC and evaluated within 1 week of injury.

INDEPENDENT VARIABLES

Patient demographics, medical history, injury description, computerized neurocognitive testing, vestibular/ocular testing, and symptoms at initial clinical visit.

MAIN OUTCOME MEASURES

Performance on clinical testing to predict recovery duration, classified as normal (<28 days) or prolonged (>28 days).

RESULTS

A total of 201 adolescent student athletes (age = 15.3 ± 1.4 years) were included (female 35%). Average recovery duration for the entire cohort was 22.3 ± 13.3 days, with 22% (n = 45) of adolescent student athletes taking >28 days to recover. The final model was 88.3% accurate in classifying normal and prolonged recovery. Predictor variables included sex, loss of consciousness, history of ocular disorder, history of concussion, performance on visual motor speed composite, visual motion sensitivity symptom provocation and near point of convergence distance, number-naming total time, and symptom count.

CONCLUSIONS

These findings suggest that using norm-based cutoffs from cognitive, oculomotor, and vestibulo-ocular testing and symptom reporting, clinicians can accurately predict a prolonged recovery (sensitivity = 81%) and normal recovery (specificity = 83%) in an adolescent, SRC cohort.

The Frequency of Low Scores on ImPACT in Adolescent Student-Athletes: Stratification by Race and Socioeconomic Status Using Multivariate Base Rates

This study examined the associations between the frequency of low scores on the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) by race and socioeconomic status (SES), using the proxy of Title I school status, among adolescent student-athletes and calculated multivariate base rates. There were 753 participants assigned to groups based on race (White: n = 430, 59.8%; Black: n = 289, 40.2%) and SES. Black student-athletes obtained more low neurocognitive test scores, which was associated with lower SES. The current study offers a resource to clinicians involved in concussion management who may wish to consider race and SES when interpreting ImPACT test performances.

A Cross-Cultural Examination of Parental Knowledge of Concussion in Three Countries

The aim of the present study was to examine and compare knowledge regarding concussion among parents of youth soccer players, ages 5-17, from the United States, Israel, and Sicily. Results revealed parents from the United States were more knowledgeable than Israeli and Sicilian parents and were more likely to have a previous history of concussion in their children, themselves, and their social contacts. The success of concussion education, programming, and legislation in the US may account for the greater knowledge of US parents and is reason to advocate for similar resources for youth athletes internationally.

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.

A-173 Clinical Cutoffs on the State–Trait Anxiety Inventory for Concussion

Objective

The State–Trait Anxiety Inventory (STAI) is a widely used measure of state anxiety with a proposed raw score cutoff of &gt;40 denoting probable clinical levels of anxiety. The mean score for high school aged individuals is approximately 40, corresponding with the 56th (male) and 51st (female) percentiles. The use of this cutoff classifies approximately 50% of individuals with clinically significant anxiety. In contrast, empirically based cut-offs (e.g., 1SD above the mean), classifies a more appropriate percentage of cases. The purpose of this study was to document the percentage of patients surpassing the proposed clinical cutoffs for the STAI using traditional and empirically based cutoffs in concussed high school athletes.

Methods

Participants were 273 concussed high school athletes (15.89 ± 1.1 yrs) who completed the STAI (Form Y-1) at their first clinical visit within 2–30 days of injury. Participants with a personal history of anxiety were excluded. The percentage of participants exceeding current clinical cutoffs for the STAI (i.e., &gt;40) and exceeding &gt;1, &gt;1.5, and &gt; 2 SD were calculated using high school normative data.

Results

Overall, 37% of participants exceeded the proposed raw score cutoff (&gt;40) for the STAI. Approximately 12%, 4%, and 2% of participants exhibited STAI scores that exceeded &gt;1, &gt;1.5, and &gt; 2 SD respectively.

Conclusions

The proposed cutoff score of &gt;40 for the STAI is overly inclusive and not appropriate for identifying probable clinical levels of state anxiety in concussed adolescent athletes. Use of empirically based cutoffs is more appropriate when attempting to identify clinically significant anxiety post-concussion.

A Population-Based Study of Pre-Existing Health Conditions in Traumatic Brain Injury

Health factors impacting both the occurrence of, and recovery from traumatic brain injury (TBI) vary in complexity, and present genuine challenges to researchers and healthcare professionals seeking to characterize injury consequences and determine prognosis. However, attempts to clarify causal links between injury characteristics and clinical outcomes (including mortality) often compel researchers to exclude pre-existing health conditions (PECs) in their samples, including psychiatric history, medication usage, and other comorbid conditions. In this pre-registered population-based study (total starting n = 939,123 patients), we examined trends in PEC incidence over 22 years in the state of Pennsylvania (1997-2019) in individuals sustaining TBI (n = 169,452) and individuals with orthopedic injury (n = 87,637). The goal was to determine how PECs interact with age and injury severity to influence short-term outcomes. A further goal was to determine whether number of PECs, or specific PEC clusters contributed to worse outcomes within the TBI cohort, compared with orthopedic injury alone. Primary findings indicate that PECs significantly influenced mortality within the TBI cohort; patients having four or more PECs were associated with approximately a two times greater likelihood of dying in acute care (odds ratio [OR] 1.9). Additionally, cluster analyses revealed four distinct PEC clusters that are age and TBI severity dependent. Overall, the likelihood of zero PECs hovers at ∼25%, which is critical to consider in TBI outcomes work and could potentially contribute to the challenges facing intervention science with regard to reproducibility of findings.

Does time since injury and duration matter in the benefits of physical therapy treatment for concussion?

Objective

To determine if there are differences in post-concussion symptom levels depending on 1) when physical therapy treatment is begun after the concussion and 2) the length of treatment.

Method

Retrospective chart review yielded 202 patients who sustained concussions and were referred for physical therapy. Participants/patients were assigned to independent groups based on time elapsed between concussion and physical therapy (0–14, 15–30, 31–60, 61–120, 121–365 days), and on months spent in treatment (1–4). Pre- and post- treatment scores were documented for the following measures: Sport Concussion Assessment Tool (SCAT), Convergence Insufficiency Symptom Survey (CISS), Dizziness Handicap Inventory (DHI), and Modified Clinical Test of Sensory Interaction on Balance (mCTSIB) using ANOVAs, with a Bonferroni-corrected p-value of p < .005.

Results

All patients demonstrated improvements with treatment, with no significant differences in outcomes for time elapsed since injury (SCAT Symptom Score ( p = .80), SCAT Symptom Severity Score ( p = .97), CISS ( p = .61), DHI ( p = .65), mCTSIB ( p = .13)); or for months in treatment (SCAT Symptom Score ( p = .23), SCAT Symptom Severity Score ( p = .04), CISS ( p = .41), DHI ( p = .37), mCTSIB ( p = .50)).

Conclusions

Improvements were similar for all patients receiving post-concussive physical therapy, regardless of time between injury and treatment onset, and regardless of time spent in treatment. These results may have implications for clinical decision-making and for third party payors’ coverage of post-concussion treatment. Longer periods of treatment may not necessarily be of greater benefit and application of treatment if delayed may also be beneficial. Limitations to the study, such as its retrospective nature, lack of randomization, and convenience sample size are discussed.

Compliance with State Concussion Legislation in Non-School-Affiliated Youth Sport Leagues

Youth league administrators (N = 172) documented knowledge of/compliance with state concussion legislation, and were assigned to groups based on whether their state concussion legislation extended to non-school-affiliated (NSA) youth sport leagues: EXTEND (50.6%) or NOT EXTEND (49.4%). Administrators within the EXTEND group were 2.7x more likely to report having a formal concussion policy. Only 90.7% confirmed a policy for removing concussed athletes from play, and 75% required independent medical clearance, and 82% mandated education for coaches, 49.1% for parents, and 35.9% for athletes. These results raise questions regarding compliance with state concussion legislation, especially for NSA youth sports leagues.

Cross-cultural exploration of baseline ImPACT Quick Test performance among football athletes in Zambia

OBJECTIVE

Concussion is a global sport injury; however, this public health issue has yet to be studied across Africa. It is unknown if tests such as the Immediate Post-Concussion Assessment and Cognitive Test (ImPACT) Quick Test (QT) are culturally appropriate for implementation as part of a concussion screening protocol in Zambia or other African nations. Study objectives included: 1) establish that Zambian athletes are able to complete the iPad-based ImPACT QT with respect to language or cultural barriers that may exist, and 2) document baseline neurocognitive percentile ranks among Zambian football athletes on the ImPACT QT.

METHODS

This study was completed with adult premiere league football athletes in Zambia (n = 125) aged 24.48 ± 5.41. Participants completed the ImPACT QT neurocognitive assessment prior to a preseason practice. Outcome measures were average performance on 3 factor scores: Motor Speed, Memory, and Attention Tracker, presented as percentile ranks using normative data built-into the ImPACT QT.

RESULTS

Zambian athletes scored nearly two standard deviations below the mean on Motor Speed (7^th percentile), using North American normative data. However, performance on Attention Tracker (44^th percentile) and Memory (56^th percentile) was within the average range.

CONCLUSION

Results of the current study show that Zambian athletes are able to complete the ImPACT QT, despite any language or cultural differences that may exist. In addition, preliminary percentile ranks suggest Zambian football athletes have average scores on Attention and Memory and below average scores on Motor Speed. These data are the first to explore Zambian athletes' performance on a cognitive concussion measure.

Using change scores on the vestibular ocular motor screening (VOMS) tool to identify concussion in adolescents

OBJECTIVE

To develop clinical cutoffs using change scores for the VOMS individual items and an overall VOMS change score that identified concussion in adolescent athletes.

METHODS

Change score clinical cutoffs were calculated from a sample of adolescents (13-18 years) with SRC (n = 147) and a sample of uninjured adolescents CONTROL (n = 147). Receiver operating characteristic (ROC) curves, with area under the curve (AUC), based on Youden's J statistic were used to identify optimal cutoffs for identifying SRC from CONTROLS using VOMS individual item change scores, an overall VOMS change scores, and NPC distance (cm).

RESULTS

AUC values for VOMS item change scores ranged from .55 to .71. Optimal change score cutoffs were ≥1 for VOMS items and ≥3 for overall VOMS change score. The optimal cutoff for NPC distance was ≥3 cm. A ROC analysis revealed a three-factor model (AUC = .76) for identifying SRC that included vertical vesibular ocular reflex (VVOR), visual motion sensitivity (VMS), and NPC distance items. The AUC (.73) for the overall VOMS change score was higher than any individual VOMS AUC values.

CONCLUSIONS

This study supports an alternate scoring approach and clinical interpretation of VOMS items involving change scores that account for pretest symptoms.

Utility of 1 Measurement Versus Multiple Measurements of Near Point of Convergence After Concussion

CONTEXT

Increased near point of convergence (NPC) distance is a common finding after concussion and is associated with physical symptoms and worsened neurocognitive performance. Vestibular/Ocular Motor Screening measures NPC distance across 3 trials and uses the average measurement to inform clinical care. However, whether 3 trials are necessary, are consistent, or add clinical utility is unknown.

OBJECTIVE

To investigate the consistency across 3 trials of NPC and establish the classification accuracy (ie, clinical utility) of 1 or 2 trials compared with the standardized average of 3 trials.

DESIGN

Retrospective cohort study.

SETTING

Sports medicine clinic and research laboratory.

PATIENTS OR OTHER PARTICIPANTS

Consecutively enrolled patients aged 10 to 22 years with diagnosed concussions (74% sport related; n = 380).

MAIN OUTCOME MEASURE(S)

The previously reported clinical cutoff value of ≥5 cm across 3 trials was used. Pearson correlation and intraclass correlation coefficients were used to evaluate agreement between trials and average scores. Reliable change indices (RCIs) using 95% confidence intervals were also calculated.

RESULTS

The Pearson correlation (r = .98) and intraclass correlation (0.98) coefficients revealed excellent agreement between the first measurement and average NPC distance across 3 measurements. The RCI across all trials was 2 cm. When the first NPC measurement was ≤3 cm or ≥7 cm, agreement existed within the RCI between the first measurement and the average of 3 measurements in 99.6% of cases. When we averaged the first and second measurements, 379/380 (99.7%) participants had the same classification (ie, <5 cm = normal, ≥5 cm = abnormal) as the average NPC distance across 3 measurements.

CONCLUSIONS

Our findings suggest limited utility of multiple or average NPC distance measurements when the initial NPC distance is outside of RCI clinical cutoffs (ie, ≤3 cm or ≥7 cm). Given the high consistency between the first measurement and average NPC distance across 3 trials, only 1 measurement of NPC distance is warranted unless the first measurement is between 3 and 7 cm.

Brief iPad-Based Assessment of Cognitive Functioning with ImPACT® Quick Test: Prevalence of Low Scores Using Multivariate Base Rates

OBJECTIVE

The ImPACT® Quick Test is a brief iPad-based battery of neurocognitive tests that has been standardized on a sample of children, adolescents, and adults (ages 12-70). This study provides information on the prevalence of ImPACT® Quick Test scores falling below specific percentiles in the normative sample to aid in clinical interpretation and reduce the risk of over-interpreting, or misinterpreting, a single low score.

METHOD

Participants were 683 individuals ranging in age from 12 to 70, who were assessed individually. The ImPACT® Quick Test includes five subtests, contributing to three factor scores: motor speed, memory, and attention tracker. The prevalence of low factor scores, stratified by age and sex, were calculated using multivariate base rates.

RESULTS

In the total sample, obtaining 1 or more scores below the 25th percentile was common (base rate, BR = 47.2%), but obtaining 2 or more scores in this range was uncommon (BR = 15.3%). Similarly, obtaining 1 or more scores below the 16th percentile was common (BR = 31.4%), but obtaining two or more scores in this range was uncommon (BR = 6.9%). There were small differences in BRs between sexes and the number of low scores was fairly similar across the age groups.

CONCLUSION

Results from this study parallel previous work illustrating that a substantial percentage of healthy individuals will obtain one or more low test scores when administered a brief battery of cognitive tests. Given that some healthy individuals will obtain a single score below expected cut-offs, clinicians should caution against overinterpreting a single low test score.

Relationship between Standalone Performance Validity Test Failure and Emotionality among Youth/student Athletes Experiencing Prolonged Recovery following Sports-related Concussion

This study documented the rate of Performance Validity Testing (PVT) failure in 81 youth athletes, aged 10-21 years, experiencing prolonged recovery following sports-related concussion, and the relationship between PVT and emotional symptoms. Neuropsychological assessments were conducted across three test sessions with a stand-alone PVT at each session. Results showed that 48% (39/81) of individuals failed at least one PVT, with an overall PVT failure rate of 26% (64/243). Those failing at least one PVT scored significantly higher on anxiety but not depression or somatization. Results illustrate the importance of including measures of emotional and behavioral functioning in testing following SRC.

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.

A-29 Incidence of Invalid ImPACT Baseline Test Results on Initial and Follow-up Assessments among English-Speaking, Spanish-Speaking, and Bilingual Test-takers

Objective

To identify the rate of ImPACT baseline test results falling below cut-offs for invalidity indicators among English-speaking, Spanish-speaking, and bilingual-speaking, individuals, upon initial assessment and on a follow-up baseline.

Method

Participants were a large sample of test-takers who completed annual ImPACT baseline assessments in Greater Houston, TX, as a requirement for participation in club- or school-sponsored athletics. Participants were 12–18 years old (mean 15.3, SD = 1.5), predominantly male (69%), and assigned to independent groups on the basis of primary/secondary language: English (N = 9332), English/Spanish (N = 1380), or Spanish (N = 4720). A sub-sample of each group (English N = 815, English/Spanish N = 173, Spanish N = 63) completed 2 baseline assessments (mean 1.2 years between tests, SD = 0.55 years).

Results

Chi-square analysis revealed a significantly greater likelihood [X2(2) = 28.05; p &lt; .001] of obtaining an invalid baseline for individuals with Spanish as a First (6.3%) or Second (6.9%) Language as compared to individuals speaking only English (4.8%), with an overall rate of 5.6% across all three groups. Upon re-assessment, 5.7% of English, 19% of English-Spanish, and 0% of Spanish-speakers obtained a second “invalid” assessment. The Three Letters (Total Correct &lt; 8) and Design Memory (Learning Percentage &lt; 50) indicators were the most common contributing indicators, across all three groups.

Conclusions

Primary language appears to be a contributing factor in scoring below cut-offs for invalidity indicators, especially for bilingual English-Spanish speakers. The continued rate of invalidity for the English-Spanish speakers on follow baseline assessments also warrants further review. Given the retrospective nature of this study, potential influences of acculturation and language proficiency were not available and therefore, could not be assessed.

A-48 Athletes that self-report no physical activity/rest are more likely to exhibit clinical levels of state anxiety following concussion

Objective

To investigate the influence of self-reported physical activity (PA) on state anxiety in athletes with concussion

Method

Participants were 230 athletes (mean age = 16.46, SD = 1.94; 43% female) seeking care for a concussion at a specialty clinic within 30 days of injury (M = 8.83, SD = 6.12 days). Demographic data were collected during the clinical interview: age, sex, and history of concussion, migraine, learning disability, attention deficit hyperactivity disorder, anxiety, and depression. Patients completed the State-Trait Anxiety Inventory (STAI) and self-reported current levels of PA; 113 participants reported rest or no physical activity (REST) and 117 reported at least minimal PA (ACTIVE). The groups were compared on demographic variables to ensure group equivalence. Independent samples t-test examined differences between groups on state anxiety scores and a chi-square with odds ratios (ORs) examined the relationship between PA groups and clinical levels of state anxiety (STAI &gt; 40). Statistical significance for all analyses was (p &lt; .05).

Results

The groups were similar on all demographic variables (p &gt; .05). The NO PA/REST group exhibited significantly higher state anxiety scores at first clinic visit than the PA group (t (228) = 2.82, p = .005), and the NO PA/REST group was 2.26 times more likely to exhibit clinical levels of state anxiety than the PA group at first clinic visit (χ2 (1, N = 230) = 9.16, p = .002).

Conclusions

Anxiety that is secondary to concussive injury could be mitigated with physical activity. Healthcare providers should encourage individuals with concussion to engage in physical activity during recovery.

A-28 Updated Baselines Show Improvement, Even When Athletes Sustain A Concussion Between Assessments

Objective

To explore change across repeated baseline assessments using raw scores and percentile scores, for athletes sustaining and not sustaining a concussion between baselines.

Method

Athletes (12–23 years) completed two valid, baseline neurocognitive test sessions using ImPACT. Participants were divided into independent groups based on having sustained a concussion between annual baselines (CONCUSSION; N = 269) or no concussion (NO CONCUSSION; N = 270) between baselines. Raw change scores were calculated between the first and follow-up baseline for both groups by subtracting the first baseline score from the updated baseline score on the four ImPACT composite scores. Age- and gender-based percentile scores were then applied for all participants, and percentile change scores were calculated in the same manner. Raw change scores and percentile change scores between groups were compared using 4 ANOVAs with a Bonferroni-corrected p-value of (p &lt; .0125).

Results

Using raw scores ANOVAs revealed that athletes in the CONCUSSION group showed significantly greater improvement on follow-up testing than athletes in the NO CONCUSSION group on Verbal Memory (p &lt; .001) and Visual Motor Speed (p = .001), but not on Visual Memory (p = .41) and Reaction Time (p = .04). Using percentile ranks, ANOVAs revealed significantly greater improvement in CONCUSSION group on Verbal Memory (p &lt; .001), but not on Visual Memory (p = .34), Visual Motor Speed (p = .03), or Reaction Time (p = .014).

Conclusions

Athletes sustaining a concussion between annual baseline assessments show increases on Verbal Memory and Visual Motor Speed follow-up testing when using raw composite scores, but only on Verbal Memory when using age- and gender-based percentile ranks.

A-38 A Different Approach for Examining Gender Differences on Computerized Neurocognitive Testing: Percentile Ranks Versus Composite Scores

Objective

ImPACT is a popular tool used to assess neurocognitive function after concussion. Age- and gender-based percentile ranks are provided as part of the ImPACT clinical report, but only raw composite scores are provided for research. Percentile ranks may provide an alternate look at gender differences on neurocognitive testing. We sought to compare the use of percentile ranks versus composite scores when comparing neurocognitive performance between male and females.

Method

Pre-season baseline data from 3,238 collegiate athletes were exported from a larger multi-site database, 1,714 male (53%) and 1,524 female (47%), ages 18–22 (Mean = 19.3, SD = 1.2). ImPACT composite scores were extracted (Verbal Memory, Visual Memory, Visual Motor Speed, Reaction Time) and Percentile Ranks were calculated using age- and gender-based reference tables in the ImPACT 2017–2012 Technical Manual. One-way analyses of variance (ANOVA) were conducted with gender as the IV and the four composite scores and their associated percentile ranks as the DVs. Bonferroni correction for 8 comparisons set the alpha level to p &lt; .006.

Results

ANOVAs revealed a significant effect of gender on ImPACT Verbal Memory [F(1,3236) = 16.32, p &lt; .001], Visual Memory [F(1,3236) = 66.06, p &lt; .001], Visual Motor Speed [F(1,3236) = 15.61,p &lt; .001] but not Reaction Time [F(1,3236) = 2.59, p = .11]. When using percentile ranks, ANOVAs revealed a significant effect of gender on only Visual Motor Speed [F(1,3236) = 31.07, p &lt; .001], but not Verbal Memory [F(1,3236) = 2.43, p = .12], Visual Memory [F(1,3236) = 0.48, p = .49], or Reaction Time [F(1,3236) = 0.61, p = .44].

Conclusions

Use of ImPACT Composite Scores in concussion research may exaggerate or inappropriately promote gender differences on computerized neurocognitive testing. Given that age- and gender-based normative data are available, use of percentile ranks is recommended.

A-06 Agree to Disagree: Evaluating the Utility of Child and Parent-Reported Symptom Summary Scores on the ImPACT Pediatric

Objective

ImPACT Pediatric is a neurocognitive test used to assess concussion in children ages 5–11. Embedded in the test is a series of yes/no symptom questions, answered by both parents and their child. The purpose of this study was to determine if there was any utility in creating summary scores using child- and parent-reported symptoms, and document agreement between child- and parent-reported symptoms.

Method

De-identified baseline and post-concussion ImPACT Pediatric data were obtained from the lead programmer at ImPACT Applications, Inc, who was blind to the purpose of the study. Number of symptoms endorsed through parent and child self-report was documented by summing individual symptoms endorsed at baseline and within 7 days of concussion. Chi-squared analyses were conducted to evaluate the level of agreement between the four symptoms that appear on both child and parent symptom lists (Headache, Dizziness, Tiredness, and Nausea/Vomiting).

Results

Across the four shared symptoms (Headache, Dizziness, Tiredness, and Nausea/Vomiting), parent- child co-endorsement ranged from 27%–71% at baseline, and 69%–95% post-concussion; Kappa (as a measure of agreement) was weak; .24–.41. Paired-samples T-tests revealed children report significantly more symptoms than their parents at baseline (p &lt; .001) but not post-concussion (p = .14).

Conclusions

Parents and their children are not in agreement with respect to symptom endorsement on the ImPACT Pediatric at baseline, with children endorsing a significantly greater number of total symptoms. While the presence/absence of specific symptoms may be of clinical utility, creating a summary symptom score out of binary symptom data does not appear to be useful.

A-36 Understanding Parental Knowledge of and Attitudes towards Youth Sport-Related Concussion

Objective

The study objective was to examine parental knowledge of, and attitudes towards, youth sport-related concussion in a Canadian sample.

Method

A community sample of seventy-six families (n = 120 children) completed the study questionnaire comprised of demographic and sport history information, as well as questions about concussion knowledge (factual and perceived) and attitudes (i.e. concussion management and treatment attitudes). All participants had children actively involved in sport. Predominantly mothers completed the questionnaire (74%), and families ranged from one-to-three children (M age = 9 yr 5mth, SD = 2 yr 11mth).

Results

On average, parents achieved 76% accuracy on factual concussion knowledge (M = 21.19, SD = 2.55), with the majority (75%) perceiving their responses as accurate (perceived knowledge). Most parents displayed a favourable attitude toward concussion reporting and management (54/63; 85.7%). Families with low social risk status (SRS) had higher perceived knowledge compared to families with high SRS (t(60) = 2.29, p = .026), but not actual knowledge (p = .87). Mixed linear regression models were used to examine relationships between sociodemographic factors and concussion knowledge and attitudes. Higher SRS (F(1,74) = 9.60, p = .003) was related to lower perceived knowledge.

Conclusions

Families with higher SRS had less confidence in their youth sport-related concussion knowledge despite having accurate knowledge. Understanding sociodemographic factors associated with concussion attitudes and knowledge is an important first step for informing policies and keeping youth active in sports.

A Cross-Cultural Examination of Parental Knowledge of Concussion in Sicily, Italy

Forty parents of youth soccer players of ages 5-17 years, in Sicily, Italy completed a survey measuring knowledge of concussion symptoms and facts. Parents averaged 16 out of 23 correct responses (69.5%) on the survey, with no significant correlation between parental age and education and knowledge. Italian parents were more familiar with somatic symptoms (92.5%-100% correct) than emotional/behavioral (27.5%-57.5% correct) and sleep symptoms (45.0%). Comparisons to U.S. and Australian research showed general agreement on knowledge of concussion symptoms, but less awareness of other concussion facts among Italian parents. More research on cross-cultural concussion education and barriers to concussion resources is warranted.

A-20 Do Children With LD and/or ADHD Differ at Baseline on a Pediatric Measure Used to Assess Concussion?

Objective

To examine differences at baseline between children with ADHD and/or LD vs. children with neither ADHD/LD on 1) neurocognitive scores and 2) child- and parent-reported concussion symptoms.

Method

Retrospective data was obtained for 1856 children ages 5–11 who were assessed at baseline using ImPACT Pediatric. Groups were determined based on parent-reported diagnosis of their child at baseline (ADHD and/or LD vs. neither ADHD/LD), and groups were compared on the four factor scores: Sequential Memory, Word Memory, Visual Memory, and Rapid Processing and on child- and parent-reported concussion symptoms using a series of ANOVAs.

Results

ANOVAs revealed that children with ADHD and/or LD performed significantly worse than children without ADHD/LD on Sequential Memory (F(1,1845) = 69.86, p &lt; .001)) and Word Memory (F(1,1853) = 10.36, p = .001)). In contrast, children with ADHD and/or LD performed significantly better on the neurocognitive measures of Visual Memory [(F(1,1845) = 4.94, p = .026)] and Rapid Processing [(F(1,1853) = 20.35, p &lt; .001). Symptom reporting was significantly greater in the ADHD and/or LD group for both child (F(1,1853) = 30.21, p &lt; .001) and parent (F(1,1853) = 34.64, p &lt; .001) reported symptoms.

Conclusions

The current study demonstrated differences at baseline in children on neurocognitive performance and concussion symptom reporting based on diagnostic group. Analysis of symptom reporting suggested that children with pre-existing diagnoses of ADHD and/or LD and their parents may report concussion-like symptoms at baseline, prior to ever experiencing a concussion. This finding has clinical implications for interpretation of post-concussion symptoms without a baseline comparison in children with pre-existing diagnoses such as ADHD and/or LD.

P1616L-2-hydroxyglutarate dehydrogenase (L2HGDH) is a novel target for heart failure due to pressure overload

Background

We have found L-2-hydroxyglutarate dehydrogenase (L2HGDH) to be downregulated in the myocardium of mice subjected to transverse aortic constriction (TAC). L2HGDH is an important regulator of mitochondrial bioenergetics by catalyzing the conversion of L-2-hydroxyglutarate (L2-HG) to α-ketoglutarate. However, the connection between L2-HG accumulation and heart failure is not yet understood.

Purpose

Purpose of our study was to investigate the role of increased L2-HG levels in heart failure and the potential role of L2HGDH overexpression as therapeutic strategy.

Methods

For in vitro studies, primary rat neonatal cardiomyocytes (NRVCMs) were incubated with L2-HG. L2HGDH was overexpressed using adeno-associated virus (AAV) 6 vectors. Mitochondrial membrane potential was measured using TMRE (tetramethylrhodamine ethyl ester) dye. Mitochondrial reactive oxygen species production was monitored using MitoSOX. We further determined activation of fetal gene program by real time qPCR and macrophage migration using RAW 264.7 cells and transwell inserts. mTOR activation was analyzed by Western blot with antibodies against phosphorylated mTOR and ribosomal protein S6. AAV9 expressing L2HGDH or luciferase was injected in C57BL/6N mice two weeks prior to TAC and heart function was monitored by echocardiography for 6 weeks.

Results

L2-HG acts as a pro-hypertrophic stimulus in NRVCMs as shown by upregulation of a fetal gene expression pattern and an increase in cardiomyocyte cross-sectional area upon L2-HG treatment. Furthermore, mRNA levels of macrophage chemoattractant protein 1 were increased in L2-HG treated cells, which correlated with enhanced macrophage migration towards supernatant of L2-HG treated NRVCMs. Furthermore, we could confirm that L2-HG augmented mTOR signaling by affecting the phosphorylation status of ribosomal protein S6. AAV-mediated L2HGDH overexpression in NRVCMs led to a significant 2.1-fold decrease in the accumulation of ROS production. Moreover, we found an inhibition of endothelin-1 induced mitochondrial membrane depolarization in AAV6-L2HGDH transduced cells.

Pretreatment of mice with AAV9-L2HGDH prior to TAC resulted in significantly reduced heart weight to tibia length ratios (HW/TL) and cardiomyocyte area. Importantly, heart function was notably improved in mice receiving gene therapy (ejection fraction, EF: 36.18±6.63%, fractional shortening, FS: 16.72±4.01%) whereas control animals showed marked decline in myocardial contractility (EF: 20.14±8.24%, FS: 12.66±6.66%).

Conclusion

L2-HG causes cardiomyocyte dysfunction by activating mTOR signaling pathway, a well-characterized critical inducer of myocyte hypertrophy, and enhancing macrophage migration, leading to establishment of a pro-inflammatory environment in the myocardium. Moreover, our results point out towards a novel preventive approach for cardiac hypertrophy and heart failure by cardiomyocyte-specific L2HGDH overexpression.

Acknowledgement/Funding

DZHK (Deutsches Zentrum für Herz-Kreislaufforschung)

The Relationship Between the Post-Concussion Symptom Scale and State-Trait Anxiety Inventory in Concussed Athletes

Purpose

To document the relationship between concussion symptoms and state anxiety in concussed adolescent athletes.

Methods

One hundred fifty-three concussed athletes (mean age=16.06, SD=1.62 yrs.) completed the Post-Concussion Symptom Scale (PCSS) and the State-Trait Anxiety Inventory (STAI) at their initial clinical visit within 30 days of injury (M=8.29, SD=6.46 days). Due to violations of normality (Shapiro-Wilk=.95), Spearman’s Rank Order correlations were conducted between STAI state scores and PCSS affective, somatic, cognitive-migraine-fatigue, and sleep clusters and total symptoms. Correlations were also conducted within sub-samples of patients seen within one week (M=3.80, SD=1.72days) and 8 – 30 days post-injury (M=13.91, SD=5.76 days). Statistical significance was set at (p<.05).

Results

In the total sample (n=153), STAI state scores were significantly associated with total symptoms (r=.54), and the affective (r=.53), sleep (r=.44), cognitive-migraine-fatigue (r=.47), and somatic (r=.33) symptom clusters. All significant relationships among STAI state scores and PCSS total symptoms and symptom clusters were retained for patients seen within 1 week as well as patients completing their first clinical visit 8-30 days post-concussion (p<.05).

Conclusion

Post-concussion endorsement of concussion symptoms increases as a function of state anxiety. Although the PCSS affective symptom cluster is not a validated measure to diagnose anxiety; these findings support the utility of the PCSS to evaluate for potentially elevated anxiety in concussed adolescent athletes.

Altitude and Concussions in the NFL: Is There Really a “Mile-High” Effect?

Purpose

The literature on altitude and concussions in football shows some evidence of protective effects of living and training and playing at high altitudes. We explored the likelihood of sustaining concussions within the AFC West division, specifically comparing games hosted at high altitude in Denver versus games hosted by at low altitudes in Los Angeles, Oakland, and Kansas City.

Methods

Information was recorded for all regular season AFC West division games (N= 42) occurring in the 2012–2018 seasons. Altitude for each stadium was calculated using DaftLogic’s Google Sandbox. Concussion incidence for the 2012–2018 seasons was collected from PBS Frontline’s Concussion-Watch and weekly injury reports (NFL.com). Chi-square analyses compared likelihood of: concussions occurring in High Altitude versus Low Altitude, a Broncos player sustaining a concussion in High Altitude versus Low Altitude, and a non-Broncos AFC West player sustain a concussion in High Altitude versus Low Altitude.

Results

Chi-square analyses revealed no greater likelihood of players sustaining concussions in High Altitude versus Low Altitude (p=.35), or of Broncos (p=1.00) or non-Broncos (p=.47) AFC West players sustaining concussions in High Altitude versus Low Altitude.

Conclusion

Altitude is not a significant factor for increased likelihood of concussions, and popular theories such as “the mile-high effect” are not supported by the data. We found no evidence for the proposed protective factor of living and training at high altitude for Broncos team members, as they showed an equal likelihood of sustaining a concussion at high and low altitude.

Addressing the ``Replication Crisis'' in Sports Neuropsychology: Validation of the Two-Factor Theory of ImPACT

Purpose

The "replication crisis" in psychology and across the broader field of social sciences raises criticism due to a lack of data to show that esoteric research findings can be replicated. The present study replicated and validated the two-factor “memory” and “speed” structure of ImPACT (Schatz & Maerlender, 2013).

Methods

High school aged athletes (N=18,918, Mean age=15.4, SD=1.2) who completed pre-season baseline ImPACT testing were randomly assigned to one of 5 independent samples of approximately 3,780 athletes. Exploratory factor analyses (FA) for a two-factor solution were conducted with ImPACT composite scores within each of the five groups. Post-Concussion Symptom Scale (PCSS) scores were included, with the expectation they would load on a third, unique factor.

Results

All five samples met assumptions for FA (KMO Measure of Sampling Adequacy above .600), and all five analyses yielded the same “memory” and “speed” two-factor structure. Visual Motor Speed and Reaction Time loaded on the first "Speed" factor and Verbal and Visual Memory loaded on a second "Memory" factor. The PCSS scores loaded on a third, unique “symptom” factor.

Conclusion

Replication of the two-factor structure for ImPACT in a five large high school sample further validates the model. Given that both visual and verbal memory involve encoding of information presented visually, use of a “memory” factor may improve interpretation of ImPACT scores. Similarly, similarities between constructs measuring speed of responding (Reaction Time) and speed of processing (Visual Motor Processing Speed) may be best explained using a “speed” factor.

Exploring Athletic Trainers' Self-Confidence for Interpreting Results from Concussion Assessments

Purpose

To explore athletic trainers' self-confidence for interpreting results from concussion assessments.

Methods

An online survey was administered via the National Athletic Trainers’ Association (NATA) membership listserv to a cross-sectional sample of 10,000 certified athletic trainers (ATCs) employed in high school and collegiate settings. The survey included: 1) ATC demographics (i.e., age, sex, years of experience); 2) ATC concussion management practices (i.e., previous concussion training, continuing education received on concussion, concussion assessments administered); and 3) a 4-point Likert scale (1=no confidence, 4=high confidence) assessing ATC self-confidence for interpreting results from concussion assessments. A total of 725 ATCs completed the survey yielding a response rate of 7.25%; 114 were excluded for missing data and 611 ATCs were included in final analyses. Sample demographics, ATC concussion management practices, and ATC self-confidence scores were examined with demographic statistics (i.e., means, standard deviations, frequencies, percentages) for 16 commonly used concussion assessments.

Results

The sample of ATCs (mean age 38.97±14.89 years) was predominately female (59.2%) and reported an average of 10.08±7.58 years of clinical experience. Clinical examinations (63.2%) and symptom scales (61.4%) were among the most frequent assessments with high ATC self-confidence for interpretation. Vestibular/oculomotor measures (27.2%) and computerized neurocognitive testing (26.2%) were among the most frequent assessments with low ATC self-confidence for interpretation.

Conclusion

Low ATC self-confidence scores for interpreting results from vestibular/oculomotor measures and computerized neurocognitive testing highlight the importance of incorporating a multi-disciplinary team approach and including sport neuropsychologists for the proper management of concussion.

Exposure to Serial Post-Concussion Neurocognitive Testing Does not Affect Future “Updated” Baseline Neurocognitive Performance in Adolescent Athletes

Purpose

We investigated a dose response for serial post-concussion neurocognitive testing exposure on updated post-concussion baseline testing performance.

Methods

Athletes (13-18 yrs) that completed two, valid baseline neurocognitive testing (ImPACT) sessions approximately 1-3 years apart participated in this study. A sub-sample of athletes that sustained a SRC between baseline sessions were categorized into dose-response groups based on the number of serial, post-concussion neurocognitive tests completed following SRC: ONE (n=76), TWO (n=99), and THREE OR MORE (n=111). Athletes that did not sustain a SRC comprised the ZERO group (n=289). Change scores between the first to the second baseline were calculated for the ImPACT Composite and Symptom Scores and compared between the dose-response groups and controls with 5 ANOVAs, with a Bonferroni-corrected p-value of (p<.01). Baseline testing was administered using ImPACT stimuli within the “Baseline” administration, and all post-concussion ImPACT testing was administered using alternate-form associated with that specific post-injury assessment (Post-Injury1, Post-Injury2, etc).

Results

ANOVAs revealed no effect of number of post-concussion assessments (0, 1, 2, or 3+) on magnitude of the change between first and final baselines, for Verbal Memory (p=.08), Visual Memory (p=.96), Visual Motor Speed (p=.47), Reaction Time (p=.91), or Total Symptom Scores (p=.86).

Conclusion

Repeated exposure to neurocognitive testing has revealed improvements in Visual Motor Speed among normal controls, across test-retest intervals of 1-month, 1-year, and 2-years. However, in this study, exposure to post-concussion, serial neurocognitive testing had no effect on future performance on post-concussion baseline neurocognitive testing.

Evaluating the Prevalence of Low Factor Scores on the ImPACT™ Quick Test in Adolescents and Adults using Multivariate Base Rates

Purpose

The ImPACT™ Quick Test (QT) is a brief iPad-based battery of neurocognitive tests that has been standardized on a sample of children, adolescents, and adults (ages 12-70). We sought to provide information regarding the prevalence of low ImPACT™ QT scores in the normative sample to improve clinical interpretation and reduce the risk of over-interpreting, or misinterpreting, a single low score.

Methods

Participants included 616 individuals ranging in age from 12 to 70, who were assessed individually. The ImPACT QT includes five subtests, contributing to three factor scores: Motor Speed, Memory, and Attention Tracker. The prevalence of low factor scores, stratified by age and gender, were calculated using multivariate base rates.

Results

In the total sample, obtaining 1 score below the 25th percentile was common (base rate, BR=31.8%), but obtaining 2 or more scores in this range was uncommon (BR=13.3%). Similarly, obtaining 1 score below the 16th percentile was common (BR=22.3%), but obtaining two or more scores in this range was very uncommon (BR=5.4%). There were small differences in base rate between genders and the number of low scores were fairly similar across the age groups.

Conclusion

Results from this study parallel previous work illustrating that a substantial percentage of healthy individuals will obtain one or more low test score when administered a battery of multiple cognitive test measures. Given that some healthy, non-concussed individuals will obtain a single score below expected cut-offs, clinicians should caution against overinterpreting a single low test score.

Does Time Since Injury and Time Spent in Physical Therapy Treatment Affect Outcomes for Concussion Patients?

Purpose

To evaluate the effects of: 1) time between injury and physical therapy treatment and 2) time spent in physical therapy, on concussion symptom resolution.

Methods

Retrospective data was obtained for 202 patients who sustained a concussion and were referred for physical therapy. Subjects were assigned to groups based on type of injury (sport-related or not), time elapsed between concussion and therapy (0-14 days, 15–30, 31–60, 61–120, 121–365), and months spent in treatment (1 thru 4). Pre- and post- treatment scores were compared for the following measures: Sport Concussion Assessment Tool (SCAT), Convergence Insufficiency Symptom Survey (CISS), Dizziness Handicap Inventory (DHI), and Modified Clinical Test of Sensory Interaction on Balance (mCTSIB) using ANOVAs, with a Bonferroni-corrected p-value of p<.005.

Results

There was no significant difference in outcomes for athletes vs. non-athletes on SCAT Symptom (p=.74) or Severity Score (p=.18), CISS (p=.52), DHI (p=.05), or mCTSIB (p=.10); in outcomes for time elapsed since injury on SCAT Symptom Score (p=.80), SCAT Symptom Severity Score (p=.97), CISS (p=.61), DHI (p=.65), mCTSIB (p=.13); or in outcomes for months in treatment on SCAT Symptom Score (p=.23), SCAT Symptom Severity Score (p=.04), CISS (p=.41), DHI (p=.37), mCTSIB (p=.50).

Conclusion

Post-therapeutic improvements were noted for athletes receiving post-concussive physical therapy. Type of injury, time between injury and treatment, and time spent in treatment did not differentiate treatment outcomes for those receiving physical therapy post-concussion.

Gender Differences in Symptom Reporting on Baseline Sport Concussion Testing Across the Youth Age Span

Background

Little is known regarding gender differences in concussion symptom reporting developmentally across the age span, specifically in pre-adolescent athletes. The present study asks: Do boys and girls differ in symptom reporting across the pre-adolescent to post-adolescent age span?

Method

This retrospective study utilized baseline assessments from 11,695 10-22 year-old athletes assigned to 3 independent groups: Pre-adolescent 10-12 year olds (n = 1,367; 12%), Adolescent 13-17 year olds (n = 2,974; 25%), and Late Adolescent 18-22 year olds (n = 7,354; 63%). Males represented 60% of the sample. Baseline ImPACT composite scores and Post-Concussion Symptom Scale scores (Total, Physical, Cognitive, Emotional, Sleep) were analyzed for the effects of age and gender.

Results

Statistically significant main effects were found for age and gender on all ImPACT composites, Total Symptoms, and Symptom factors. Significant interaction effects were noted between age and gender for all ImPACT composites, Total Symptoms, and Symptom factors. Total Symptoms and all Symptom factors were highest in adolescents (ages 13-17) for males and females. In the 10-12 age group, females displayed lower Total Symptoms, Physical, and Sleep factors than males.

Conclusion

The notion of females being more likely than males to report symptoms does not appear to apply across the developmental age span, particularly prior to adolescence. Females show greater emotional endorsement across the youth age span (10-22 years). Adolescence (13-17 years) appears to be a time of increased symptomatology that may lessen after the age of 18.

Brief iPad-Based Assessment of Cognitive Functioning with ImPACT® Pediatric

ImPACT® Pediatric is an examiner-administered iOS-based battery of neuropsychological tests designed to measure neurocognitive functioning in children ages 5-11. This study documented Multivariate Base Rates (prevalence of low scores when multiple test scores are considered simultaneously) in the ImPACT® Pediatric standardization sample (N = 892). In the total sample, it was common for children to obtain at least one low factor score using the 25th percentile [T 43; base rate (BR) = 54.2%], 16th percentile (T40, BR = 38.1%), and the 10th percentile (T37, BR = 31.1%). However, it was uncommon for children to obtain two (or more) low factor scores using any of the above-listed cutoff score.

The Age Variable in Childhood Concussion Management: A Systematic Review

Background

Sports-related concussion in young children has become a significant international public health issue. This paper reviews the research literature in an effort to shed light on the question, "At what age should young children be managed differently than adults or older adolescents?"

Method

A systematic review, registered with PROSPERO and using PRISMA guidelines, was conducted rendering 37 sports concussion original research studies that examined age as a variable (5-18 years), and which met specific inclusion/exclusion criteria.

Findings

There are no defined, evidence-based age groups for childhood concussion to substantiate differential management across the childhood and adolescent age span. There is evidence to support: (1) concussion may present differently across developmental stages; (2) with increasing age, adolescents may exhibit more symptoms from concussion; (3) the age range of 12-13 is the most frequently used cutoff point between younger and older children; (4) sports concussion research has classified the age variable in children in a number of manners: educational, developmental, sport level, or as a continuous variable, or matter of sample convenience; and (5) four general groupings of young versus pre-puberty child and early versus late adolescent are often utilized.

Conclusions

Due to limited measures and challenges of assessing younger children, current research presents a limited understanding of childhood concussion. Studies in children often lack explained rationales or theories behind age groupings or cutoffs. There is a need for studies dedicated to the question of how concussion varies developmentally from preschool through late adolescence to guide diagnosis and management.

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.