Stephen W Marshall

University of North Carolina at Chapel Hill, North Carolina, United States

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Publications (218)841.76 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Little research has examined concussion outcomes in terms of impact location (ie, the area on the head in which the impact occurred). This study describes the epidemiology of concussions resulting from player-to-player collision in high school football by impact location.
    Pediatrics. 08/2014;
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    AOSSM Annual Meeting, Seattle, WA; 07/2014
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    ABSTRACT: An athlete is thought to reduce head acceleration after impact by contracting the cervical musculature, which increases the effective mass of the head.
    The American journal of sports medicine. 06/2014;
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    ABSTRACT: A headform is needed to validate and compare helmet- and mouthguard-based sensors that measure the severity and direction of football head impacts. Our goal was to quantify the dynamic response of a mandibular load-sensing headform (MLSH) and to compare its performance and repeatability to an unmodified Hybrid III headform. Linear impactors in two independent laboratories were used to strike each headform at six locations at 5.5 m/s and at two locations at 3.6 and 7.4 m/s. Impact severity was quantified using peak linear acceleration (PLA) and peak angular acceleration (PAA), and direction was quantified using the azimuth and elevation of the PLA. Repeatability was quantified using coefficients of variation (COV) and standard deviations (SD). Across all impacts, PLA was 1.6 ± 1.8 g higher in the MLSH than in the Hybrid III (p = 0.002), but there were no differences in PAA (p = 0.25), azimuth (p = 0.43) and elevation (p = 0.11). Both headforms exhibited excellent or acceptable repeatability for PLA (HIII:COV = 2.1 ± 0.8%, MLSH:COV = 2.0 ± 1.2%, p = 0.98), but site-specific repeatability ranging from excellent to poor for PAA (HIII:COV = 7.2 ± 4.0%, MLSH:COV = 8.3 ± 5.8%, p = 0.58). Direction SD were generally <1° and did not vary between headforms. Overall, both headforms are similarly suitable for validating PLA in sensors that measure head impact severity in football players, however their utility for validating sensor PAA values varies with impact location.
    Annals of Biomedical Engineering 06/2014;
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    ABSTRACT: Background : Since 1982, the National Collegiate Athletic Association has used the Injury Surveillance System (ISS) to collect injury and athlete-exposure data from a representative sample of collegiate institutions and sports. At the start of the 2004-2005 academic year, a Web-based ISS replaced the paper-based platform previously used for reporting injuries and exposures. Objective : To describe the methods of the Web-based National Collegiate Athletic Association ISS for data collection as implemented from the 2004-2005 to 2013-2014 academic years. Description : The Web-based ISS monitored National Collegiate Athletic Association-sanctioned practices and competitions, the number of participating student-athletes, and time-loss injuries during the preseason, regular season, and postseason in 25 collegiate sports. Starting in the 2009-2010 academic year, non-time-loss injuries were also tracked. Efforts were made to better integrate ISS data collection into the workflow of collegiate athletic trainers. Data for the 2004-2005 to 2013-2014 academic years are available to researchers through a standardized application process available at the Datalys Center Web site. Conclusions : As of February 2014, more than 1 dozen data sets have been provided to researchers. The Datalys Center encourages applications for access to the data.
    Journal of athletic training. 05/2014;
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    ABSTRACT: Abstract Primary objective: To summarize the factors associated with athletes' disclosure-and non-disclosure-of sports-related concussion and concussion symptoms within the context of the socio-ecological framework and to identify research gaps in the current literature. Methods: Searches using electronic databases identified studies written in English, published through October 2013 and addressing some aspect of disclosure of concussion and concussion symptoms. The literature search aimed to be comprehensive and inclusive of all previous contributions. Main outcomes and results: Of the 30 identified studies, most originated from the US (n = 19) and sampled athletes (n = 21) and coaches (n = 10) from high school (n = 11) and college levels (n = 9). The identified reasons for non-disclosure were organized into four levels using the socio-ecological framework: intra-personal (e.g. lack of knowledge; internal pressure; sex; concussion history; n = 20 studies); inter-personal (e.g. others' knowledge/attitudes; external pressure; external support; n = 15 studies); environment (e.g. access to concussion prevention materials; sports culture; n = 4 studies); and policy (e.g. concussion-related legislation; n = 3 studies). No study examined all four levels. Conclusions: Research gaps exist concerning factors influencing athletes' disclosure of sports-related concussions and concussion symptoms. Notably, researchers have focused on intra-personal and inter-personal levels, placing less emphasis on the environment and policy levels.
    Brain Injury 04/2014; · 1.51 Impact Factor
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    ABSTRACT: There is limited evidence describing methods and challenges for implementing anterior cruciate ligament (ACL) injury prevention programs (IPP) in a "real-world" context. Evaluate the effects of a ACL IPP workshop on elite-division youth soccer coaches' behavioral determinants to implement a ACL IPP, and describe coaches' subsequent ACL IPP implementation compliance. Descriptive study. Elite-division youth soccer club. A convenient sample of 34 soccer coaches (age=34.6±9.1 yrs) of elite-division youth soccer club teams. We administered a workshop aimed at increasing coaches' behavioral determinants to implement a ACL IPP. Coaches were provided with instructional materials following the workshop. Coaches' behavioral determinants regarding ACL IPP using pre/post-workshop surveys and coaches' subsequent rate and fidelity of implementation of the ACL IPP during the following soccer season. Wilcoxon signed-rank tests indicated the workshop increased coach attitude toward; conducting a ACL IPP (P=.020), substituting a ACL IPP for a warm-up (P=.007), and improving player cutting and landing technique by implementing a ACL IPP (P=.001). The workshop increased coaches' perceived behavioral control; coaches felt more comfortable in their ability to teach their team a ACL IPP (P=.002) and more confident leading a ACL IPP if given instructions (P=.025). The workshop increased coaches' intent to implement a ACL IPP the next season (P<.001); for 15 minutes (P=.008) and 20 minutes (P=.011) prior to the start of a training session. Only 53% of the club's teams implemented the ACL IPP, with implementers demonstrating high variability in program fidelity. ACL IPP workshops can effectively increase coach attitudes, perceived behavioral control, and intent to implement a ACL IPP. However, amplification of behavioral determinants does not appear to directly translate to high-level implementation compliance. Future research should investigate supplementary strategies to facilitate optimal ACL IPP implementation to improve compliance.
    British journal of sports medicine 04/2014; 48(7):595. · 3.67 Impact Factor
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    ABSTRACT: Context : Of the individuals able to return to sport participation after an anterior cruciate ligament(ACL) injury, up to 25% will experience a second ACL injury. This population may be more sensitive to hormonal fluctuations, which may explain this high rate of second injury. Objective : To examine changes in 3-dimensional hip and knee kinematics and kinetics during a jump landing and to examine knee laxity across the menstrual cycle in women with histories of unilateral noncontact ACL injury. Design : Controlled laboratory study. Setting : Laboratory. Patients or Other Participants : A total of 20 women (age = 19.6 ± 1.3 years, height = 168.6 ± 5.3 cm, mass = 66.2 ± 9.1 kg) with unilateral, noncontact ACL injuries. Intervention(s) : Participants completed a jump-landing task and knee-laxity assessment 3 to 5 days after the onset of menses and within 3 days of a positive ovulation test. Main Outcome Measure(s) : Kinematics in the uninjured limb at initial contact with the ground during a jump landing, peak kinematics and kinetics during the loading phase of landing, anterior knee laxity via the KT-1000, peak vertical ground reaction force, and blood hormone concentrations (estradiol-β-17, progesterone, free testosterone). Results : At ovulation, estradiol-β-17 (t = -2.9, P = .009), progesterone (t = -3.4, P = .003), and anterior knee laxity (t = -2.3, P = .03) increased, and participants presented with greater knee valgus moment (Z = -2.6, P = .01) and femoral internal rotation (t = -2.1, P = .047). However, during the menses test session, participants landed harder (greater peak vertical ground reaction force; t = 2.2, P = .04), with the tibia internally rotated at initial contact (t = 2.8, P = .01) and greater hip internal-rotation moment (Z = -2.4, P = .02). No other changes were observed across the menstrual cycle. Conclusions : Knee and hip mechanics in both phases of the menstrual cycle represented a greater potential risk of ACL loading. Observed changes in landing mechanics may explain why the risk of second ACL injury is elevated in this population.
    Journal of athletic training 02/2014; · 1.68 Impact Factor
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    ABSTRACT: Information as to how anterior cruciate ligament (ACL) injury and reconstructive surgery (ACLR) alter lower extremity biomechanics may improve rehabilitation and return to play guidelines, reducing the risk for repeat ACL injury. To compare lower extremity biomechanics before ACL injury and after subsequent ACLR for the injured and uninjured leg. Baseline unilateral lower extremity biomechanics were collected on the dominant leg of participants without ACL injury when they entered the Joint Undertaking to Monitor and Prevent ACL (JUMP-ACL) study. Thirty-one participants with subsequent ACL injury, reconstructive surgery and full return to physical activity completed repeat, follow-up biomechanical testing, as did 39 uninjured, matched controls. Not all injured participants suffered injury to the dominant leg, requiring separation of those with ACL injury into two groups: ACLR-injured leg group (n=12) and ACLR-uninjured leg group (n=19). We compared the landing biomechanics of these three groups (ACLR-injured leg, ACLR-uninjured leg, control) before ACL injury (baseline) with biomechanics after ACL injury, surgery and return to physical activity (follow-up). ACL injury and ACLR altered lower extremity biomechanics, as both ACLR groups demonstrated increases in frontal plane movement (increased hip adduction and knee valgus). The ACLR-injured leg group also exhibited decreased sagittal plane loading (decreased anterior tibial shear force, knee extension moment and hip flexion moment). No high-risk biomechanical changes were observed in control group participants. ACL injury and ACLR caused movement pattern alterations of the injured and uninjured leg that have previously shown to increase the risk for future non-contact ACL injury.
    British journal of sports medicine 02/2014; · 3.67 Impact Factor
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    ABSTRACT: Approximately 6500 high school football athletes are treated annually for exertional heat illness (EHI). In 2009, the National Athletic Trainers Association (NATA)-led Inter-Association Task Force (NATA-IATF) released preseason heat acclimatization guidelines to help athletes become accustomed to environmental factors contributing to EHI. This study examines compliance with NATA-IATF guidelines and related EHI prevention strategies. The study used a cross-sectional survey completed by 1142 certified athletic trainers (AT), which captured compliance with 17 NATA-IATF guidelines and EHI prevention strategies in high school football during the 2011 preseason. On average, AT reported football programs complying with 10.4 NATA-IATF guidelines (SD = 3.2); 29 AT (2.5%) reported compliance with all 17. Guidelines with the lowest compliance were as follows: "Single-practice days consisted of practice no more than three hours in length" (39.7%); and "During days 3-5 of acclimatization, only helmets and shoulder pads should be worn" (39.0%). An average of 7.6 EHI prevention strategies (SD = 2.5) were used. Common EHI prevention strategies were as follows: having ice bags/cooler available (98.5%) and having a policy with written instructions for initiating emergency medical service response (87.8%). Programs in states with mandated guidelines had higher levels of compliance with guidelines and greater prevalence of EHI prevention strategies. A low proportion of surveyed high school football programs fully complied with all 17 NATA-IATF guidelines. However, many EHI prevention strategies were voluntarily implemented. State-level mandated EHI prevention guidelines may increase compliance with recognized best practices recommendations. Ongoing longitudinal monitoring of compliance is also recommended.
    Medicine and science in sports and exercise 01/2014; 46(1):124-130. · 4.48 Impact Factor
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    ABSTRACT: Context: For individuals able to return to sport after an Anterior Cruciate Ligament (ACL) injury, up to 25% will experience a second ACL injury. This population may be more sensitive to hormonal fluctuations, which may potentially explain this high second injury rate. Objective: The purpose of this study was to examine changes in three dimensional hip and knee kinematics and kinetics during a jump landing as well as knee laxity across the menstrual cycle in females with a history of unilateral non-contact ACL injury. Design: Repeated measures. Setting: Laboratory. Patients or Other Participants: 20 females with unilateral noncontact ACL injury. Interventions: Subjects completed a jump landing task and knee laxity assessment, 3-5 days after the onset of menses and within 3 days following a positive ovulation test. Main Outcome Measures: Kinematics in the healthy limb were examined at initial contact with the ground during a jump landing; Peak kinematics and kinetics during the loading phase of landing; Anterior knee laxity via the KT-1000; Peak vertical ground reaction force. Blood hormone levels (Estradiol-β-17, Progesterone, Free Testosterone). Results: Estradiol-β-17 (P=.009), Progesterone (P=.003), and anterior knee laxity (P=.03) increased at ovulation and participants presented with greater knee valgus moment (P=.01) and femoral internal rotation (P=.04). However, participants landed harder (greater peak vertical ground reaction force) during the menses test session (P=.04) with the tibia internally rotated at initial contact (P=.01) and greater hip internal rotation moment (P=.02). No other significant changes were observed across the menstrual cycle. Conclusions: Knee and hip mechanics in both phases of the menstrual cycle represent a greater risk of loading. Observed changes in landing mechanics may potentially explain why ACL risk of second ACL injury is elevated in this population. Keywords: Hormones, Estrogen, Knee, Vertical Ground Reaction Force, Knee Valgus Moment
    Journal of athletic training 01/2014; · 1.68 Impact Factor
  • Clinics in Sports Medicine. 01/2014;
  • Karen G Roos, Stephen W Marshall
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    ABSTRACT: A number of epidemiologic and surveillance-based studies of sports injury provide statistics on, and sometimes discussion of, overuse injuries. However, there is no consensus on the definition of "overuse." Some studies consider "overuse" as a mechanism of injury while others use a diagnosis-based definition. The objective of this study was to describe variation between studies in the definition and use of the term "overuse." PubMed and SPORTDiscus databases were searched between May and November 2012 to find articles published or online ahead of printing pertaining to US high school or collegiate athletics, which were epidemiologic in nature. Inclusion criteria required that the article present data collected on athlete exposure and provided statistics pertaining to overuse injuries. PRISMA guidelines were adhered to, to the best ability of the authors. The initial search resulted in 5,182 articles with potential for inclusion. After review of titles or abstracts where appropriate, 232 studies were read in entirety to determine if they were appropriate for inclusion. Of the 35 articles included, 13 used data from the National Collegiate Athletics Association's Injury Surveillance System, 12 used data from the High School Reporting Information Online (RIO) injury surveillance system, and one used data from both of these systems. The remaining nine articles used data from distinct surveillance systems or prospectively collected data. All of these articles included data on overuse injuries, although not all provided definitions for overuse. A major finding from the literature is that the term "overuse" has been used both as a mechanism of injury and as an injury diagnosis (or a category of diagnoses). Specifically, of 35 articles, 14 used "overuse" as a mechanism of injury, seven used it as a category of injury diagnoses, eight used it as both a category of injury diagnoses and a mechanism of injury, and it was unclear in one how the term is used. Only one of the 35 articles provided a biomechanical definition for overuse injuries. Twelve of 35 articles combined "overuse" with other terms such as "chronic," "gradual onset," and "repetitive stress." Use of the term "no contact" was investigated in relation to "overuse." Four of 35 articles define overuse in the context of no contact injuries. Only one of 35 articles define "no contact" as a specific acute mechanism of injury, while all other mentions of "no contact" do not specifically distinguish whether "no contact" was limited to acute injuries only, or has potential to include "overuse" injuries. There is a great deal of inconsistency in the use of the term "overuse" both within and between data sources. This is further complicated by the multiple uses of the term "no contact." We recommend that the term "overuse" only be used in regard to the mechanism of injury in order to enhance interpretation and understanding of the literature regarding overuse injuries and enhance the ability to compare results between studies. We also recommend the adoption of a common working definition of overuse injuries within injury surveillance. This definition should emphasize that overuse injuries are characterized by (1) a mechanism of gradual onset, and (2) an underlying pathogenesis of repetitive microtrauma.
    Sports medicine (Auckland, N.Z.). 11/2013;
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    ABSTRACT: Motor vehicle crashes are a leading cause of serious trauma during pregnancy, but little is known about their relationships with pregnancy outcomes. To estimate the association between motor vehicle crashes and adverse pregnancy outcomes. A retrospective cohort study of 878,546 pregnant women, aged 16-46 years, who delivered a singleton infant in North Carolina from 2001 to 2008. Pregnant drivers in crashes were identified by probabilistic linkage of vital records and crash reports. Poisson regression modeled the association among crashes, vehicle safety features, and adverse pregnancy outcomes. Analyses were conducted in 2012. In 2001-2008, 2.9% of pregnant North Carolina women were drivers in one or more crashes. After a single crash, compared to not being in a crash, pregnant drivers had slightly elevated rates of preterm birth (adjusted rate ratio [aRR]=1.23, 95% CI=1.19, 1.28); placental abruption (aRR=1.34, 95% CI=1.15, 1.56); and premature rupture of the membranes (PROM; aRR=1.32, 95% CI=1.21, 1.43). Following a second or subsequent crash, pregnant drivers had more highly elevated rates of preterm birth (aRR=1.54, 95% CI=1.24, 1.90); stillbirth (aRR=4.82, 95% CI=2.85, 8.14); placental abruption (aRR=2.97, 95% CI=1.60, 5.53); and PROM (aRR=1.95, 95% CI=1.27, 2.99). Stillbirth rates were elevated following crashes involving unbelted pregnant drivers (aRR=2.77, 95% CI=1.22, 6.28) compared to belted pregnant drivers. Crashes while driving during pregnancy were associated with elevated rates of adverse pregnancy outcomes, and multiple crashes were associated with even higher rates of adverse pregnancy outcomes. Crashes were especially harmful if drivers were unbelted.
    American journal of preventive medicine 11/2013; 45(5):629-36. · 4.24 Impact Factor
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    ABSTRACT: BACKGROUND:The 5-year period of 2005-2009 saw more exertional heat stroke-related deaths in organized sports than any other 5-year period in the past 35 years. The risk of exertional heat stroke appears highest in football, particularly during the preseason. PURPOSE:To estimate the incidence of exertional heat stroke events and assess the utilization of exertional heat stroke management strategies during the 2011 preseason in United States high school football programs. STUDY DESIGN:Cross-sectional study; Level of evidence, 3. METHODS:A self-administered online questionnaire addressing the incidence of exertional heat stroke events and utilization of exertional heat stroke management strategies (eg, removing athlete's football equipment, calling Emergency Medical Services [EMS]) was completed in May to June 2012 by 1142 (18.0%) athletic trainers providing care to high school football athletes during the 2011 preseason. RESULTS:Among all respondents, 20.3% reported treating at least 1 exertional heat stroke event. An average of 0.50 ± 1.37 preseason exertional heat stroke events were treated per program. Athletic trainers responding to exertional heat stroke reported using an average of 6.6 ± 1.8 management strategies. The most common management strategies were low-level therapeutic interventions such as removing the athlete's football equipment (98.2%) and clothing (77.8%) and moving the athlete to a shaded area (91.6%). Few athletic trainers reported active management strategies such as calling EMS (29.3%) or using a rectal thermometer to check core body temperature (0.9%). Athletic trainers in states with mandated preseason heat acclimatization guidelines reported a higher utilization of management strategies such as cooling the athlete through air conditioning (90.1% vs 65.0%, respectively; P < .001), immersion in ice water (63.0% vs 45.4%, respectively; P = .01), or fans (54.3% vs 42.0%, respectively; P = .06) and monitoring the athlete's temperature (60.5% vs 46.2%, respectively; P = .04). CONCLUSION:Preseason exertional heat stroke events, which are likely to be fatal if untreated, were reported by one fifth of all athletic trainers in high school football programs. The standard of care is (and should be) to treat proactively; therefore, treatment is not a perfect proxy for incidence. Nevertheless, there is an urgent need for improved education and awareness of exertional heat stroke in high school football. Areas of improvement include the greatly increased use of rectal thermometers and immersion in ice water.
    The American journal of sports medicine 09/2013; · 3.61 Impact Factor
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    ABSTRACT: Construction workers are at high risk of work-related musculoskeletal back disorders, and research suggests medical care and costs associated with these conditions may be covered by sources other than workers' compensation (WC). Little is known about the back injury experience and care seeking behavior among drywall installers, a high-risk workgroup regularly exposed to repetitive activities, awkward postures, and handling heavy building materials. Among a cohort of 24,830 Washington State union carpenters (1989-2008), including 5,073 drywall installers, we identified WC claims, visits for health care covered through union-provided health insurance and time at risk. Rates of work-related overexertion back injuries (defined using WC claims data) and health care utilization for musculoskeletal back disorders covered by private health insurance were examined and contrasted over time and by worker characteristics, stratified by type of work (drywall installation, other carpentry). Drywall installers' work-related overexertion back injury rates exceeded those of other carpenters (adjusted IRR 1.63, 95% CI 1.48-1.78). For both carpentry groups, rates declined significantly over time. In contrast, rates of private healthcare utilization for musculoskeletal back disorders were similar for drywall installers compared to other carpenters; they increased over time (after the mid-1990s), with increasing years in the union, and with increasing numbers of work-related overexertion back injuries. Observed declines over time in the rate of work-related overexertion back injury, as based on WC claims data, is encouraging. However, results add to the growing literature suggesting care for work-related conditions may be being sought outside of the WC system. Am. J. Ind. Med. © 2013 Wiley Periodicals, Inc.
    American Journal of Industrial Medicine 08/2013; · 1.97 Impact Factor
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    AOSSM Annual Meeting, Chicago, IL; 07/2013
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    ABSTRACT: Context : Many athletes continue to participate in practices and games while experiencing concussion-related symptoms, potentially predisposing them to subsequent and more complicated brain injuries. Limited evidence exists about factors that may influence concussion-reporting behaviors. Objective : To examine the influence of knowledge and attitude on concussion-reporting behaviors in a sample of high school athletes. Design : Cross-sectional study. Setting : Participants completed a validated survey instrument via mail. Patients or Other Participants : A total of 167 high school athletes (97 males, 55 females, 5 sex not indicated; age = 15.7 ± 1.4 years) participating in football, soccer, lacrosse, or cheerleading. Intervention(s) : Athlete knowledge and attitude scores served as separate predictor variables. Main Outcome Measure(s) : We examined the proportion of athletes who reported continuing to participate in games and practices while symptomatic from possible concussion and the self-reported proportion of recalled concussion and bell-ringer events disclosed after possible concussive injury. Results : Only 40% of concussion events and 13% of bell-ringer recalled events in the sample were disclosed after possible concussive injury. Increased athlete knowledge of concussion topics (increase of 1 standard deviation = 2.8 points) was associated with increased reporting prevalence of concussion and bell-ringer events occurring in practice (prevalence ratio [PR] = 2.27, 95% confidence interval [CI] = 1.60, 3.21) and the reporting prevalence of bell-ringer-only events overall (PR = 1.87, 95% CI = 1.38, 2.54). Athlete attitude scores (increase of 1 standard deviation = 11.5 points) were associated with decreases in the proportion of athletes stating they participated in games (PR = 0.74, 95% CI = 0.66, 0.82) and practices (PR = 0.67, 95% CI = 0.59, 0.77) while symptomatic from concussions. Conclusions : Most recalled concussion events in our study were not reported to a supervising adult. Clinicians should be aware that knowledge and attitude influence concussion reporting. Clinicians and administrators should make concussion education a priority and encourage an optimal reporting environment to better manage and prevent concussive injuries in young athletes.
    Journal of athletic training 07/2013; · 1.68 Impact Factor
  • Silvia Ferrite, Vilma S Santana, Stephen W Marshall
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    ABSTRACT: BACKGROUND: We investigated the interaction between exposure to noise and smoking in relation to prevalence of hearing loss among women. METHODS: A sample of women aged 20-49 years (n = 1,723) from a population-based cross-sectional study carried out in Brazil in 2006 was examined. Hearing loss was assessed using a yes-no validated question. Biological interaction was analyzed using the additive scale and measured with interaction contrast ratio (ICR) and assessment of dose-response relationship. RESULTS: The combined effect of exposure to noise and cigarette smoking on hearing loss (adjusted prevalence ratio (PRadj ) = 3.94, 95% confidence interval (CI): 2.81, 5.52) was greater than expected based on the additive single effects of smoking (PRadj = 1.39, 95% CI: 1.07, 1.81) and noise (PRadj = 2.66, 95% CI: 1.86, 3.82). ICR estimates were not statistically significant. The prevalence of hearing loss among noise-exposed women increased with duration of smoking (P trend = 0.026), number of cigarettes smoked per day (P trend = 0.034), cumulative tobacco use (P trend = 0.030), and early age at smoking initiation (P trend = 0.047). CONCLUSIONS: Noise and smoking may have a combined effect on hearing loss but further studies are still needed. A dose-response relation of smoking for the noise effect among women is suggested. Am. J. Ind. Med. © 2013 Wiley Periodicals, Inc.
    American Journal of Industrial Medicine 06/2013; · 1.97 Impact Factor
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    ABSTRACT: BACKGROUND:Headache-related symptoms may be predictive of delayed recovery in student athletes after sport-related concussion.Purpose and HYPOTHESIS:To compare balance performance, cognitive function, and symptom recovery in concussed student athletes with no headache, those with posttraumatic headache, and those with characteristics of posttraumatic migraine following a sport-related concussion. It was hypothesized that those with posttraumatic migraine would take longer to recover on all clinical measures. STUDY DESIGN:Cohort study (prognosis); Level of evidence, 2. METHODS:A total of 296 student athletes who sustained sport-related concussions (migraine, 52; headache, 176; no headache, 68) were evaluated on measures of balance performance, cognition, and symptoms. Patients were categorized into posttraumatic migraine, posttraumatic headache, and no headache groups based on symptoms reported 1 day after injury. Serial testing was conducted with the Balance Error Scoring System, the Standardized Assessment of Concussion, and a graded symptom checklist to evaluate balance performance, cognition, and symptoms, respectively, at baseline, at the time of injury, after the event, and at days 1, 2, 3, 5, 7, and 90. RESULTS:Student athletes with posttraumatic migraine experienced greater symptom severity scores than did those with posttraumatic headache and no headache at the time of injury, after the event, and through day 7 (P < .001 for all). By day 7, symptom severity scores reported by patients with posttraumatic migraine still demonstrated deficits relative to baseline (Δ = 5.6 ± 1.2) compared with patients with headache (Δ = -0.8 ± 0.7) and those with no headache (Δ = -1.4 ± 1.1). Patients with headache experienced greater symptom severity scores than patients with no headache at the time of injury (P < .001), after the event (P < .001), and at day 1 (P < .001), day 2 (P = .005), and day 3 (P = .038). Much smaller differences were observed between the headache and no headache groups beyond day 3 (P > .05). There were no group differences on balance performance (P = .439) and cognitive testing (P = .200) over time. Female patients were 2.13 times more likely than males to report posttraumatic migraine characteristics after concussion. CONCLUSION:Posttraumatic migraine characteristics are related to prolonged symptom recovery after sport-related concussion. Clinicians should exercise caution in making decisions about return to participation for athletes with migraine-like symptoms given the increased short-term impairments and delayed symptom recovery we observed.
    The American journal of sports medicine 05/2013; · 3.61 Impact Factor

Publication Stats

6k Citations
841.76 Total Impact Points


  • 1993–2014
    • University of North Carolina at Chapel Hill
      • • Department of Exercise and Sport Science
      • • Department of Epidemiology
      • • Department of Emergency Medicine
      • • Department of Maternal and Child Health
      North Carolina, United States
  • 2013
    • WakeMed Health & Hospitals
      Raleigh, North Carolina, United States
  • 2011–2013
    • State of California
      California City, California, United States
    • Universidade Federal da Bahia
      • Departamento de Fonoaudiologia
      Bahia, Estado de Bahía, Brazil
    • United States Air Force
      New York City, New York, United States
  • 2012
    • Medical College of Wisconsin
      Milwaukee, Wisconsin, United States
  • 2010–2011
    • University of Connecticut
      • Department of Kinesiology
      Storrs, CT, United States
    • United States Army
      Washington, West Virginia, United States
    • Duke University Medical Center
      • Department of Community and Family Medicine
      Durham, NC, United States
  • 2009–2011
    • University of Georgia
      • Department of Kinesiology
      Athens, GA, United States
    • University of Nevada, Reno
      Reno, Nevada, United States
    • University of Virginia
      • Department of Public Health Sciences
      Charlottesville, VA, United States
  • 2008
    • University of Utah
      • Department of Pediatrics
      Salt Lake City, UT, United States
  • 1993–1997
    • University of Otago
      • • Department of Preventive & Social Medicine
      • • Injury Prevention Research Unit
      Dunedin, Otago, New Zealand
  • 1994
    • Population Services International
      Washington, Washington, D.C., United States