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Browsing by Author "Kontos, Anthony P."
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Item Bifactor Model of the Sport Concussion Assessment Tool Symptom Checklist: Replication and Invariance Across Time in the CARE Consortium Sample(Sage, 2020-09) Brett, Benjamin L.; Kramer, Mark D.; McCrea, Michael A.; Broglio, Steven P.; McAllister, Thomas; Nelson, Lindsay D.; Hazzard, Joseph B., Jr.; Kelly, Louise A.; Ortega, Justus; Port, Nicholas; Pasquina, Paul F.; Jackson, Jonathan; Cameron, Kenneth L.; Houston, Megan N.; Goldman, Joshua T.; Giza, Christopher; Buckley, Thomas; Clugston, James R.; Schmidt, Julianne D.; Feigenbaum, Luis A.; Eckner, James T.; Master, Christina L.; Collins, Michael W.; Kontos, Anthony P.; Chrisman, Sara P.D.; Duma, Stefan M.; Miles, Christopher M.; Susmarski, Adam; Psychiatry, School of MedicineBackground: Identifying separate dimensions of concussion symptoms may inform a precision medicine approach to treatment. It was previously reported that a bifactor model identified distinct acute postconcussion symptom dimensions. Purpose: To replicate previous findings of a bifactor structure of concussion symptoms in the Concussion Assessment Research and Education (CARE) Consortium sample, examine measurement invariance from pre- to postinjury, and evaluate whether factors are associated with other clinical and biomarker measures. Study design: Cohort study (Diagnosis); Level of evidence, 2. Methods: Collegiate athletes were prospectively evaluated using the Sport Concussion Assessment Tool-3 (SCAT-3) during preseason (N = 31,557); 2789 were followed at <6 hours and 24 to 48 hours after concussion. Item-level SCAT-3 ratings were analyzed using exploratory and confirmatory factor analyses. Bifactor and higher-order models were compared for their fit and interpretability. Measurement invariance tested the stability of the identified factor structure across time. The association between factors and criterion measures (clinical and blood-based markers of concussion severity, symptom duration) was evaluated. Results: The optimal structure for each time point was a 7-factor bifactor model: a General factor, on which all items loaded, and 6 specific factors-Vestibulo-ocular, Headache, Sensory, Fatigue, Cognitive, and Emotional. The model manifested strict invariance across the 2 postinjury time points but only configural invariance from baseline to postinjury. From <6 to 24-48 hours, some dimensions increased in severity (Sensory, Fatigue, Emotional), while others decreased (General, Headache, Vestibulo-ocular). The factors correlated with differing clinical and biomarker criterion measures and showed differing patterns of association with symptom duration at different time points. Conclusion: Bifactor modeling supported the predominant unidimensionality of concussion symptoms while revealing multidimensional properties, including a large dominant General factor and 6 independent factors: Headache, Vestibulo-ocular, Sensory, Cognitive, Fatigue, and Emotional. Unlike the widely used SCAT-3 symptom severity score, which declines gradually after injury, the bifactor model revealed separable symptom dimensions that have distinct trajectories in the acute postinjury period and different patterns of association with other markers of injury severity and outcome. Clinical relevance: The SCAT-3 total score remains a valuable, robust index of overall concussion symptom severity, and the specific factors identified may inform management strategies. Because some symptom dimensions continue to worsen in the first 24 to 48 hours after injury (ie, Sensory, Fatigue, Emotional), routine follow-up in this time frame may be valuable to ensure that symptoms are managed effectively.Item Estimated age of first exposure to American football and outcome from concussion(Wolters Kluwer, 2020-11-24) Caccese, Jaclyn B.; Houck, Zac; Kaminski, Thomas W.; Clugston, James R.; Iverson, Grant L.; Bryk, Kelsey N.; Oldham, Jessie R.; Pasquina, Paul F.; Broglio, Steven P.; McAllister, Thomas W.; McCrea, Michael; Reed Hoy, April Marie; Hazzard, Joseph B., Jr.; Kelly, Louise A.; Ortega, Justus D.; Port, Nicholas; Putukian, Margot; Langford, T. Dianne; Giza, Christopher C.; Goldman, Joshua T.; Benjamin, Holly J.; Schmidt, Julianne D.; Feigenbaum, Luis A.; Eckner, James T.; Mihalik, Jason P.; Dysart Miles, Jessica; Anderson, Scott; Master, Christina L.; Collins, Micky W.; Kontos, Anthony P.; Chrisman, Sara P.D.; Brooks, Alison; Jackson, Jonathan C.; McGinty, Gerald; Cameron, Kenneth L.; Susmarski, Adam; O'Donnell, Patrick G.; Duma, Stefan; Rowson, Steve; Miles, Christopher M.; Bullers, Christopher T.; Dykhuizen, Brian H.; Lintner, Laura; Buckley, Thomas A.; Psychiatry, School of MedicineObjective: To examine the association between estimated age at first exposure (eAFE) to American football and clinical measures throughout recovery following concussion. Methods: Participants were recruited across 30 colleges and universities as part of the National Collegiate Athletic Association (NCAA)-Department of Defense Concussion Assessment, Research and Education Consortium. There were 294 NCAA American football players (age 19 ± 1 years) evaluated 24-48 hours following concussion with valid baseline data and 327 (age 19 ± 1 years) evaluated at the time they were asymptomatic with valid baseline data. Participants sustained a medically diagnosed concussion between baseline testing and postconcussion assessments. Outcome measures included the number of days until asymptomatic, Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) composite scores, Balance Error Scoring System (BESS) total score, and Brief Symptom Inventory 18 (BSI-18) subscores. The eAFE was defined as participant's age at the time of assessment minus self-reported number of years playing football. Results: In unadjusted regression models, younger eAFE was associated with lower (worse) ImPACT Visual Motor Speed (R 2 = 0.031, p = 0.012) at 24-48 hours following injury and lower (better) BSI-18 Somatization subscores (R 2 = 0.014, p = 0.038) when the athletes were asymptomatic. The effect sizes were very small. The eAFE was not associated with the number of days until asymptomatic, other ImPACT composite scores, BESS total score, or other BSI-18 subscores. Conclusion: Earlier eAFE to American football was not associated with longer symptom recovery, worse balance, worse cognitive performance, or greater psychological distress following concussion. In these NCAA football players, longer duration of exposure to football during childhood and adolescence appears to be unrelated to clinical recovery following concussion.Item King-Devick Sensitivity and Specificity to Concussion in Collegiate Athletes(Allen Press, 2023) Le, Rachel Khinh; Ortega, Justus; Chrisman, Sara P.; Kontos, Anthony P.; Buckley, Thomas A.; Kaminski, Thomas W.; Meyer, Briana P.; Clugston, James R.; Goldman, Joshua T.; McAllister, Thomas; McCrea, Michael; Broglio, Steven P.; Schmidt, Julianne D.; Psychiatry, School of MedicineContext: The King-Devick (K-D) test is used to identify oculomotor impairment after concussion. However, the diagnostic accuracy of the K-D test over time has not been evaluated. Objectives: To (1) examine the sensitivity and specificity of the K-D test at 0 to 6 hours postinjury, 24 to 48 hours postinjury, the beginning of a return-to-play (RTP) protocol (asymptomatic), unrestricted RTP, and 6 months postconcussion and (2) compare outcomes between athletes with and those without concussion across confounding factors (sex, age, sport contact level, academic year, learning disorder, attention-deficit/hyperactivity disorder, migraine history, concussion history, and test administration mode). Design: Retrospective, cross-sectional design. Setting: Multiple institutions in the Concussion Assessment, Research and Education Consortium. Patients or other participants: A total of 320 athletes with a concussion (162 men, 158 women; age = 19.80 ± 1.41 years) were compared with 1239 total collegiate athletes without a concussion (646 men, 593 women; age = 20.31 ± 1.18 years). Main outcome measure(s): We calculated the K-D test time difference (in seconds) by subtracting the baseline from the most recent time. Receiver operator characteristic (ROC) curve and area under the curve (AUC) analyses were used to determine the diagnostic accuracy across time points. We identified cutoff scores and corresponding specificity at both the 80% and 70% sensitivity levels. We repeated ROC with AUC analyses using confounding factors. Results: The K-D test predicted positive results at the 0- to 6-hour (AUC = 0.724, P < .001), 24- to 48-hour (AUC = 0.701, P < .001), RTP (AUC = 0.640, P < .001), and 6-month postconcussion (AUC = 0.615, P < .001) tim points but not at the asymptomatic time point (AUC = 0.513, P = .497). The 0- to 6-hour and 24- to 48-hour time points yielded 80% sensitivity cutoff scores of -2.6 and -3.2 seconds (ie, faster), respectively, but 46% and 41% specificity, respectively. The K-D test had a better AUC when administered using an iPad (AUC = 0.800, 95% CI = 0.747, 0.854) compared with the spiral-bound card system (AUC = 0.646, 95% CI = 0.600, 0.692; P < .001). Conclusions: The diagnostic accuracy of the K-D test was greatest at 0 to 6 hours and 24 to 48 hours postconcussion but declined across subsequent postconcussion time points. The AUCs did not differentiate between groups across confounding factors. Our negative cutoff scores indicated that practice effects contributed to improved performance, requiring athletes to outperform their baseline scores.Item Mechanisms of injury for concussions in collegiate soccer: an NCAA/DoD CARE consortium study(Taylor & Francis, 2022) Kaminski, Thomas W.; Chrismanh, Sara P. D.; Glutting, Joseph; Wahlquist, Victoria; Eagle, Shawn; Putukian, Margot; Tierney, Ryan; Broglio, Steven P.; McAllister, Thomas W.; McCrea, Michael A.; Pasquina, Paul F.; Kontos, Anthony P.; CARE Site Investigators; Psychology, School of ScienceObjective: The purpose of this study was to describe the mechanism of injury (MOI) and examine factors associated with greater risk for specific MOIs involving concussions in collegiate soccer players. Methods: Participants included 3,288 collegiate soccer players from 28 institutions across four competitive seasons, 2014-17. MOIs were documented for 262 soccer-related concussions during the study and placed into one of four categories: collisions, unintentional contact, aerial challenges, and others. Results: 70% of the concussions occurred in DI soccer players. Collisions and unintentional contact were the MOIs that resulted in 66.5% of all concussions. DI and DIII soccer players sustained more concussions by unintentional contact versus collisions and aerial challenges when compared to their DII counterparts. Defenders were more likely than midfielders to sustain concussions by aerial challenges than collisions. As expected, the field players experienced more concussions as a result of collisions, unintentional contact, and aerial challenges when compared to goalkeepers. Conclusions: Future research should explore preventive strategies for decreasing collisions, especially during aerial challenges while heading the soccer ball, and unintentional contacts from errant balls in soccer in order to decrease concussion risk.Item Relationship Between the King-Devick Test and Commonly Used Concussion Tests at Baseline(Allen Press, 2019-12) Clugston, James R.; Houck, Zachary M.; Asken, Breton M.; Boone, Jonathan K.; Kontos, Anthony P.; Buckley, Thomas A.; Schmidt, Julianne D.; Chrisman, Sara P.D.; Hoffman, Nicole L.; Harmon, Kimberly G.; Kaminski, Thomas W.; Collins, Michael W.; McAllister, Thomas W.; McCrea, Michael A.; Broglio, Steven P.; Ortega, Justus D.; Psychiatry, School of MedicineContext: Comprehensive assessments are recommended to evaluate sport-related concussion (SRC). The degree to which the King-Devick (KD) test adds novel information to an SRC evaluation is unknown. Objective: To describe relationships at baseline among the KD and other SRC assessments and explore whether the KD provides unique information to a multimodal baseline concussion assessment. Design: Cross-sectional study. Setting: Five National Collegiate Athletic Association institutions participating in the Concussion Assessment, Research and Education (CARE) Consortium. Patients or other participants: National Collegiate Athletic Association student-athletes (N = 2258, age = 20 ± 1.5 years, 53.0% male, 68.9% white) in 11 men's and 13 women's sports. Main outcome measure(s): Participants completed baseline assessments on the KD and (1) the Symptom Inventory of the Sport Concussion Assessment Tool-3rd edition, (2) the Brief Symptom Inventory-18, (3) the Balance Error Scoring System, (4) the Standardized Assessment of Concussion (SAC), (5) the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) test battery, and (6) the Vestibular/Ocular Motor Screening tool during their first year in CARE. Correlation coefficients between the KD and the 6 other concussion assessments in isolation were determined. Assessments with ρ magnitude >0.1 were included in a multivariate linear regression analysis to evaluate their relative association with the KD. Results: Scores for SAC concentration, ImPACT visual motor speed, and ImPACT reaction time were correlated with the KD (ρ = -0.216, -0.276, and 0.164, respectively) and were thus included in the regression model, which explained 16.8% of the variance in baseline KD time (P < .001, Cohen f2 = 0.20). Better SAC concentration score (β = -.174, P < .001), ImPACT visual motor speed (β = -.205, P < .001), and ImPACT reaction time (β = .056, P = .020) were associated with faster baseline KD performance, but the effect sizes were small. Conclusions: Better performance on cognitive measures involving concentration, visual motor speed, and reaction time was weakly associated with better baseline KD performance. Symptoms, psychological distress, balance, and vestibular-oculomotor provocation were unrelated to KD performance at baseline. The findings indicate limited overlap at baseline among the CARE SRC assessments and the KD.Item Test–Retest Reliability of Computerized Neurocognitive Testing in Youth Ice Hockey Players(Oxford University Press, 2016-06) Womble, Melissa N.; Reynolds, Erin; Schatz, Philip; Shah, Kishan M.; Kontos, Anthony P.; Orthopaedic Surgery, School of MedicineComputerized neurocognitive tests are frequently used to assess pediatric sport-related concussions; however, only 1 study has focused on the test–retest reliability of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) in high school athletes and age influences have largely been ignored. Therefore, the purpose was to investigate the test–retest reliability of ImPACT and underlying age influences in a pediatric population. Two hundred (169 men and 31 women) youth ice hockey players completed ImPACT before/after a 6-month season. Reliability was assessed using Pearson correlation coefficients, intraclass correlation coefficients (ICCs), and regression-based methods (RBz). ICCs for the sample ranged from .48 to .75 (single)/.65 to .86 (average). In general, the older athletes (15–18: Single/Average ICCs = .35–.75/.52–.86) demonstrated greater reliability across composites than the younger athletes (11–14: Single/Average ICCs = .54–.63/.70–.77). Although there was variation in athletes' performance across two test administrations, RBz revealed that only a small percentage of athletes performed beyond 80%, 90%, and 95% confidence intervals. Statistical metrics demonstrated reliability coefficients for ImPACT composites in a pediatric sample similar to previous studies, and also revealed important age-related influences.