Stephen W Marshall

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

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Publications (238)909.65 Total impact

  • Zachary Kerr, Stephen W. Marshall, Johna Register-Mihalik
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    ABSTRACT: Background: Recurrent concussion may result in neuro-dementia. However, athletes may not disclose sport-related concussion symptoms to others. Research is needed on factors influencing nondisclosure of concussion symptoms by athletes. Methods: Former collegiate athletes who played between 1987-2012 (n=797) completed an online self-administered questionnaire about impacts sustained during sport participation that should have been diagnosed by team medical staff as concussions, but were not. We asked why concussions went undiagnosed and what sources of information influenced respondents’ knowledge of concussions. Results: Of the 214 respondents self-reporting sport-related concussions (26.9% of sample), 44.9% stated that they had sustained impacts that should have been diagnosed by medical staff as concussions, but were not. Common reported factors associated with non-diagnosis were not telling team medical staff (33.2%) and no team medical staff being present (19.2%). Among those with non-disclosed concussions, common self-reported reasons for non-disclosure included: not wanting to leave the game/practice (78.9%); not wanting to let team down (71.8%); and not knowing it was a concussion (70.4%). Sources of knowledge that helped respondents realize impacts may have been undiagnosed concussions were continuing education (20.8%); friends (14.6%); and the media (71.9%), particularly ESPN (32.3%). Conclusion: Among those former collegiate athletes self-reporting sport-related concussions, nearly half of former collegiate athletes reported sustaining undiagnosed sport-related concussions. External influences such as perceived peer expectations and media coverage were influential in former athletes’ concussion reporting. This information may assist in refining public health campaigns that seek to improve disclosure of symptoms (e.g. CDC’s Heads-Up program).
    142nd APHA Annual Meeting and Exposition 2014; 11/2014
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    ABSTRACT: Background: Young athletes suffering from a concussion should be assessed by a trained health care provider. However, many concussions are never diagnosed because children and their parents do not seek care. We examined whether parents’ knowledge and attitudes towards concussion were associated with post-concussion care-seeking for their children. Methods: A cohort of 214 youth sport parents [(63% female; parent age: 44.1(±6.5 yrs); child age: 11.6±(1.9 yrs)] completed a pre-validated concussion knowledge (max possible score=28), attitudes (max possible score=63) and care-seeking survey. Higher knowledge and attitude scores represented more favorable scores. Parents reported number of: diagnosed concussions, times their child displayed signs/symptoms of concussion following a head impact, and care-seeking behaviors following these events. The main outcome was care-seeking for all potential concussions (all-care group) vs. not (lower-care group). Results: Twenty-six percent (n=55) of parents reported that their child had ≥ 1 potential concussion. The majority of these parents (72%, n=40) did not follow-up with a medical provider after each event. Mean attitude score was 51.5(±1.6) in the all-care group and 48.1(±4.2) in the lower-care group. Mean knowledge score was 23.6(±2.5) in the all-care group and 23.6±(2.9) in the lower-care group. More favorable parental attitudes towards concussion were positively associated with care-seeking (OR: 1.7; 95% CI: 1.1, 2.8). Parents’ knowledge was not associated with better care-seeking (OR: 0.9; 95% CI: 0.7, 1.3). Conclusions: While concussion knowledge is undoubtedly important, parental attitudes were more important in predicting care-seeking. Future parental interventions should stress the importance of prompt care for all potential concussions.
    142nd APHA Annual Meeting and Exposition 2014; 11/2014
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    ABSTRACT: To compare the odds of sustaining moderate and severe head impacts, rather than mild, between high school football players with high and low visual performance.
    Clinical journal of sport medicine: official journal of the Canadian Academy of Sport Medicine 11/2014; · 1.50 Impact Factor
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    ABSTRACT: Musculoskeletal injuries during military and sport-related training are common, costly, and potentially debilitating. There is a need to develop and implement evidence-based injury prevention strategies to reduce the burden of musculoskeletal injury. The lack of attention to implementation issues is a major factor limiting the ability to successfully reduce musculoskeletal injury rates using evidence-based injury prevention programs. This article proposes 7 steps that can be used to facilitate successful design and implementation of evidence-based injury prevention programs within the logical constraints of a real-world setting by identifying implementation barriers and associated solutions.
    Clinics in Sports Medicine. 10/2014;
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    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; · 3.23 Impact Factor
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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
  • 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: Municipal waste water sludge contains microbes and toxicants and is commonly applied to land. Some neighbors of land application sites report sludge-associated malodors and illness. We evaluated sludge and livestock odors, 14 physical symptoms, and quality of life indicators reported by neighbors of fields applied with class-B sludge and residents of comparison areas with no sludge application, and measured concentrations of brominated flame retardants on pine needles as an indicator of sludge aerosol dispersal. 157 adults living near liquid sludge application sites, 85 near cake application sites, and 188 in comparison areas responded to a household survey. Sludge exposure was classified as none or faint vs. moderate, strong, or very strong sludge odor separately for residents of liquid and cake application vs. comparison areas. Livestock odor was classified as none or faint vs. moderate, strong, or very strong. We identified upper respiratory, lower respiratory, gastrointestinal, and skin symptom factors by principle components analysis. Generalized estimating equations (GEE) linear models were used to compare factor scores for sludge and livestock odor adjusted for race, gender, education, smoking, passive smoking, and odors from burning and agricultural chemicals. Adjusted factor scores for lower respiratory symptoms (standard error) were 0.280.19 higher among residents who reported moderate to very strong odor from liquid sludge than in comparison areas, and 0.280.11 higher among residents who reported moderate to very strong livestock odor compared to no or faint livestock odor. Factor scores for skin symptoms were 0.270.21 higher for participants who reported moderate to very strong liquid sludge odor. Other factor scores were similar between groups. GEE logistic models of specific symptoms suggest that wheezing contributes most to the association of lower respiratory symptoms with liquid sludge, and that difficulty breathing, cough and wheezing contribute most to its association with livestock odor.
    141st APHA Annual Meeting and Exposition 2013; 11/2013
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    ABSTRACT: Background: Research has examined concussion events by impact location (i.e., the area on the head in which impact occurs). However, little research exists regarding impact location's association with concussion-related outcomes, such as symptomatology, symptom resolution time, and length of time until return to play. Methods: National High School Sports-Related Injury Surveillance Study data (2008/09 to 2011/12) were analyzed to calculate rates and describe circumstances of football concussion by impact location (i.e., front-, back-, side-, and top-of-the-head). Results: The concussion rate was 5.1 per 100,000 athlete exposures (AEs) (95% Confidence Interval [CI]: 4.8, 5.4), with most concussions occurring from front-of-the-head impacts (57.1%) followed by side-of-the-head (27.9%), back-of-the-head (7.5%), and top-of-the-head impacts (7.4%). Most concussions were caused by head-to-head contact (70.0%), followed by contact with another body site (e.g., elbow, knee) (23.9%), and contact with playing surface (following player-player contact) (6.1%). The number of symptoms reported, symptom resolution time, and length of time to return to play were not associated with impact location. However, a higher proportion of football players sustaining concussions from top-of-the-head impacts experienced loss of consciousness (8.8%) than those sustaining concussions from impacts to other areas of the head (3.3%) (IPR [Injury Proportion Ratio]: 2.7; 95% CI: 1.4, 5.4; P=0.01). Conclusion: These findings support calls for better enforcement of rules prohibiting players from initiating contact with the top of the head and better education of players regarding proper tackling technique.
    141st APHA Annual Meeting and Exposition 2013; 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

Publication Stats

6k Citations
909.65 Total Impact Points


  • 1993–2014
    • University of North Carolina at Chapel Hill
      • • Department of Epidemiology
      • • Department of Exercise and Sport Science
      • • 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
    • United States Military Academy
      • Department of Mathematical Sciences
      West Point, New York, United States
    • 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
  • 2008–2011
    • University of Georgia
      • Department of Kinesiology
      Athens, GA, United States
    • University of Utah
      • Department of Pediatrics
      Salt Lake City, UT, United States
  • 2009
    • University of Nevada, Reno
      Reno, Nevada, United States
    • University of Virginia
      • Department of Public Health Sciences
      Charlottesville, VA, 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
  • 1991–1993
    • Wellington Hospital
      Веллингтон, England, United Kingdom