Stephen W Marshall

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

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Publications (243)1046.37 Total impact

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    ABSTRACT: Purpose: Previous studies indicate that teachers have higher asthma prevalence than other non-industrial worker groups. Schools frequently have trouble maintaining indoor relative humidity (RH) within the optimum range (30-50 %) for reducing allergens and irritants. However, the potential relationship between classroom humidity and teachers' health has not been explored. Thus, we examined the relationship between classroom humidity levels and respiratory symptoms among North Carolina teachers. Methods: Teachers (n = 122) recorded daily symptoms, while data-logging hygrometers recorded classroom RH levels in ten North Carolina schools. We examined effects of indoor humidity on occurrence of symptoms using modified Poisson regression models for correlated binary data. Results: The risk of asthma-like symptoms among teachers with classroom RH >50 % for 5 days was 1.27 (95 % Confidence Interval (CI) 0.81, 2.00) times the risk among the referent (teachers with classroom RH 30-50 %). The risk of cold/allergy symptoms among teachers with classroom RH >50 % for 5 days was 1.06 (95 % CI 0.82, 1.37) times the risk among the referent. Low RH (<30 %) for 5 days was associated with increased risk of asthma-like [risk ratio (RR) = 1.26 (95 % CI 0.73, 2.17)] and cold/allergy symptoms [RR = 1.11 (95 % CI 0.90, 1.37)]. Conclusions: Our findings suggest that prolonged exposure to high or low classroom RH was associated with modest (but not statistically significant) increases in the risk of respiratory symptoms among teachers.
    No preview · Article · Jan 2016 · International Archives of Occupational and Environmental Health
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    ABSTRACT: Background: Knowledge is limited regarding how long improvements in biomechanics remain after completion of a lower extremity injury prevention program. Purpose: To evaluate the effects of an injury prevention program on movement technique and peak vertical ground-reaction forces (VGRF) over time compared with a standard warm-up (SWU) program. Study design: Controlled laboratory study. Methods: A total of 1104 incoming freshmen (age range, 17-22 years) at a military academy in the United States volunteered to participate. Participants were cluster-randomized by military company to either the Dynamic Integrated Movement Enhancement (DIME) injury prevention program or SWU. A random subsample of participants completed a standardized jump-landing task at each time point: immediately before the intervention (PRE), immediately after (POST), and 2 (POST2M), 4 (POST4M), 6 (POST6M), and 8 months (POST8M) after the intervention. VGRF data collected during the jump-landing task were normalized to body weight (%BW). The Landing Error Scoring System (LESS) was used to evaluate movement technique during the jump landing. The change scores (Δ) for each variable (LESS, VGRF) between the group's average value at PRE and each time point were calculated. Separate univariate analyses of variance were performed to evaluate group differences. Results: The results showed a greater decrease in mean (±SD) VGRF in the DIME group compared with the SWU group at all retention time points: POST2M (SWU [Δ%BW], -0.13 ± 0.82; DIME, -0.62 ± 0.91; P = .001), POST4M (SWU, -0.15 ± 0.98; DIME,-0.46 ± 0.64; P = .04), POST6M (SWU, -0.04 ± 0.96; DIME, -0.53 ± 0.83; P = .004), and POST8M (SWU, 0.38 ± 0.95; DIME, -0.11 ± 0.98; P = .003), but there was not a significant improvement in the DIME group between PRE and POST8M (Δ%BW, -0.11 ± 0.98). No group differences in Δ LESS were observed. Conclusion: The study findings demonstrated that an injury prevention program performed as a warm-up can reduce vertical ground-reaction forces compared with a standard warm-up but a maintenance program is likely necessary in order for continued benefit. Clinical relevance: Injury prevention programs may need to be performed constantly, or at least every sport season, in order for participants to maintain the protective effects against injury.
    No preview · Article · Jan 2016 · The American Journal of Sports Medicine
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    ABSTRACT: Purpose: To determine the association between injury history at enrollment and incident lower extremity (LE) injury during cadet basic training among first-year military cadets. Methods: Medically treated LE injuries during cadet basic training documented in the Defense Medical Surveillance System (DMSS) were ascertained in a prospective cohort study of three large U.S. military academies from 2005-2008. Both acute injuries (ICD-9 codes in the 800-900s, including fracture, dislocations, sprains/strains) and injury-related musculoskeletal injuries (ICD-9 codes in the 700s, including inflammation and pain, joint derangement, stress fracture, sprain/strain/rupture, and dislocation) were included. Risk ratios (RR) and 95% confidence intervals (CI) were computed using multivariate log-binomial models stratified by gender. Results: During basic training there were 1,438 medically treated acute and 1,719 musculoskeletal-related LE injuries in the 9,811 cadets. The most frequent LE injuries were sprains/strains (73.6% of acute) and inflammation and pain (89.6% of musculoskeletal-related). The overall risk of incident LE injury was 23.2% [95%CI: 22.3%, 24.0%]. Cadets with a previous history of LE injury were at increased risk for incident LE injury. This association was identical in males (RR=1.74 [1.55, 1.94]) and females (RR=1.74 [1.52, 1.99]). In site-specific analyses, strong associations between injury history and incident injury were observed for hip, knee ligament, stress fracture, and ankle sprain. Injury risk was greater (p<0.01) for females (39.1%) compared to males (18.0%). The elevated injury risk in females (RR=2.19 [2.04, 2.36]) was independent of injury history (adjusted RR=2.09 [1.95, 2.24]). Conclusion: Injury history upon entry to the military is associated with incidence of LE injuries sustained during cadet basic training. Prevention programs targeted at modifiable factors in cadets with a prior history of LE injury should be considered.
    No preview · Article · Jan 2016 · Medicine and science in sports and exercise
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    ABSTRACT: Context: Research is limited on the extent and nature of the care provided by athletic trainers (ATs) to student-athletes in the high school setting. Objective: To describe the methods of the National Athletic Treatment, Injury and Outcomes Network (NATION) project and provide the descriptive epidemiology of AT services for injury care in 27 high school sports. Design: Descriptive epidemiology study. Setting: Athletic training room (ATR) visits and AT services data collected in 147 high schools from 26 states. Patients or other participants: High school student-athletes participating in 13 boys' sports and 14 girls' sports during the 2011-2012 through 2013-2014 academic years. Main outcome measure(s): The number of ATR visits and individual AT services, as well as the mean number of ATR visits (per injury) and AT services (per injury and ATR visit) were calculated by sport and for time-loss (TL) and non-time-loss (NTL) injuries. Results: Over the 3-year period, 210 773 ATR visits and 557 381 AT services were reported for 50 604 injuries. Most ATR visits (70%) were for NTL injuries. Common AT services were therapeutic activities or exercise (45.4%), modalities (18.6%), and AT evaluation and reevaluation (15.9%), with an average of 4.17 ATR visits (SD = 6.52) and 11.01 AT services (SD = 22.86) per injury. Compared with NTL injuries, TL injuries accrued more ATR visits (7.76 versus 3.47; P < .001) and AT services (18.60 versus 9.56; P < .001) per injury. An average of 2.24 AT services (SD = 1.33) were reported per ATR visit. Compared with TL injuries, NTL injuries had a larger average number of AT services per ATR visit (2.28 versus 2.05; P < .001). Conclusions: These findings highlight the broad spectrum of care provided by ATs to high school student-athletes and demonstrate that NTL injuries require substantial amounts of AT services.
    Full-text · Article · Dec 2015 · Journal of athletic training
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    ABSTRACT: Sports-related injuries can have a substantial impact on the long-term health of student-athletes. The National Collegiate Athletic Association (NCAA) monitors injuries among college student-athletes at member schools. In academic year 2013-14, a total of 1,113 member schools fielded 19,334 teams with 478,869 participating student-athletes in NCAA championship sports (i.e., sports with NCAA championship competition) (1). External researchers and CDC used information reported to the NCAA Injury Surveillance Program (NCAA-ISP) by a sample of championship sports programs to summarize the estimated national cumulative and annual average numbers of injuries during the 5 academic years from 2009-10 through 2013-14. Analyses were restricted to injuries reported among student-athletes in 25 NCAA championship sports. During this period, 1,053,370 injuries were estimated to have occurred during an estimated 176.7 million athlete-exposures to potential injury (i.e., one athlete's participation in one competition or one practice). Injury incidence varied widely by sport. Among all sports, men's football accounted for the largest average annual estimated number of injuries (47,199) and the highest competition injury rate (39.9 per 1,000 athlete-exposures). Men's wrestling experienced the highest overall injury rate (13.1 per 1,000) and practice injury rate (10.2 per 1,000). Among women's sports, gymnastics had the highest overall injury rate (10.4 per 1,000) and practice injury rate (10.0 per 1,000), although soccer had the highest competition injury rate (17.2 per 1,000). More injuries were estimated to have occurred from practice than from competition for all sports, with the exception of men's ice hockey and baseball. However, injuries incurred during competition were somewhat more severe (e.g., requiring ≥7 days to return to full participation) than those acquired during practice. Multiple strategies are employed by NCAA and others to reduce the number of injuries in organized sports. These strategies include committees that recommend rule and policy changes based on surveillance data and education and awareness campaigns that target both athletes and coaches. Continued analysis of surveillance data will help to understand whether these strategies result in changes in the incidence and severity of college sports injuries.
    Full-text · Article · Dec 2015 · MMWR. Morbidity and mortality weekly report
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    ABSTRACT: Background: Previous studies examining nondisclosure among athletes in various settings have found substantial proportions of athletes with undisclosed concussions. Substantial gaps exist in our understanding of the factors influencing athletes' disclosure of sports-related concussions. Purpose: To examine the prevalence of, and factors associated with, nondisclosure of recalled concussions in former collegiate athletes. Study design: Cross-sectional study; Level of evidence, 3. Methods: Former collegiate athletes (N = 797) completed an online questionnaire. Respondents recalled self-identified sports-related concussions (SISRCs) that they sustained while playing sports in high school, college, or professionally, and whether they disclosed these SISRCs to others. Respondents also recalled motivations for nondisclosure. The prevalence of nondisclosure was calculated among those who recalled SISRCs. Multivariate binomial regression estimated adjusted prevalence ratios (PRs) with 95% CIs, controlling for sex, level of contact in sports, and year the athletes began playing collegiate sports. Results: A total of 214 respondents (26.9%) reported sustaining at least 1 SISRC. Of these, 71 (33.2%) reported not disclosing at least 1 SISRC. Former football athletes were most likely to report nondisclosure (68.3% of those recalling SISRCs); female athletes who participated in low/noncontact sports were the least likely to report nondisclosure (11.1% of those recalling SISRC). The prevalence of nondisclosure was higher among men than women in the univariate analysis (PR, 2.88; 95% CI, 1.62-5.14), multivariate analysis (PR, 2.11; 95% CI, 1.13-3.96), and multivariate analysis excluding former football athletes (PR, 2.11; 95% CI, 1.12-3.94). The most commonly reported motivations were as follows: did not want to leave the game/practice (78.9%), did not want to let the team down (71.8%), did not know it was a concussion (70.4%), and did not think it was serious enough (70.4%). Conclusion: Consistent with previous studies, a substantial proportion of former athletes recalled SISRCs that were not disclosed. Male athletes were less likely to disclose all of their SISRCs than female athletes.
    No preview · Article · Nov 2015 · The American Journal of Sports Medicine
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    ABSTRACT: Background: Scuba diving mishaps, caused by equipment problems or human errors, increase the occurrence of injuries and fatalities while diving. Pre-dive checklists may mitigate mishaps. This study evaluated the effect of using a pre-dive checklist on the incidence of diving mishaps in recreational divers. Methods: A multi-location cluster-randomized trial with parallel groups and allocation concealment was conducted between 1 June and 17 August 2012. The participants had to be at least 18 years of age, permitted to dive by the dive operator and planning to dive on the day of participation. They were recruited at the pier and dive boats at four locations. The intervention group received a pre-dive checklist and post-dive log. The control group received a post-dive log only. The outcomes, self-reported major and minor mishaps, were prompted by a post-dive questionnaire. Mishap rates per 100 dives were compared using Poisson regression with generalized estimating equations. Intent-to-treat, per-protocol and marginal structural model analyses were conducted. Results: A total of 1043 divers (intervention = 617; control = 426) made 2041 dives, on 70 location-days (intervention = 40; control = 30) at four locations. Compared with the control group, the incidence of major mishaps decreased in the intervention group by 36%, minor mishaps by 26% and all mishaps by 32%. On average, there was one fewer mishap in every 25 intervention dives. Conclusions: In this trial, pre-dive checklist use prevented mishaps which could lead to injuries and fatalities. Pre-dive checklists can increase diving safety and their use should be promoted. Trial registration: ID NCT01960738.
    No preview · Article · Nov 2015 · International Journal of Epidemiology
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    ABSTRACT: Background: American youth football leagues are typically structured using either age-only (AO) or age-and-weight (AW) playing standard conditions. These playing standard conditions group players by age in the former condition and by a combination of age and weight in the latter condition. However, no study has systematically compared injury risk between these 2 playing standards.
    Full-text · Article · Sep 2015
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    Caroline F Finch · Stephen W Marshall

    Preview · Article · Sep 2015 · British Journal of Sports Medicine
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    ABSTRACT: Wearable sensors can measure head impact frequency and magnitude in football players. Our goal was to quantify the impact detection rate and validity of the direction and peak kinematics of two wearable sensors: a helmet system (HITS) and a mouthguard system (X2). Using a linear impactor, modified Hybrid-III headform and one helmet model, we conducted 16 impacts for each system at 12 helmet sites and 5 speeds (3.6-11.2 m/s) (N = 896 tests). Peak linear and angular accelerations (PLA, PAA), head injury criteria (HIC) and impact directions from each device were compared to reference sensors in the headform. Both sensors detected ~96% of impacts. Median angular errors for impact directions were 34° for HITS and 16° for X2. PLA, PAA and HIC were simultaneously valid at 2 sites for HITS (side, oblique) and one site for X2 (side). At least one kinematic parameter was valid at 2 and 7 other sites for HITS and X2 respectively. Median relative errors for PLA were 7% for HITS and -7% for X2. Although sensor validity may differ for other helmets and headforms, our analyses show that data generated by these two sensors need careful interpretation.
    No preview · Article · Aug 2015 · Annals of Biomedical Engineering
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    ABSTRACT: The Garífuna, an ethnic minority group in Honduras, have been disproportionately affected by HIV. Previous research suggests that migration and high rates of multiple sexual partnerships are major drivers of the epidemic. Using data from a 2012 population-based survey, we assessed whether temporary migration was associated with (1) multiple sexual partnerships and (2) sexual concurrency among Garífuna men and women in Honduras. Among both men and women, temporary migration in the last year was associated with an increased likelihood of multiple sexual partnerships and with concurrency, though only the association between migration and multiple sexual partnerships among men was statistically significant (Adjusted Prevalence Ratio 1.7, 95 % CI 1.2-2.4). Migration may contribute to HIV/STI vulnerability among Garífuna men and women via increases in these sexual risk behaviors. Research conducted among men and women at elevated risk of HIV should continue to incorporate measures of mobility, including history of internal migration.
    No preview · Article · Aug 2015 · AIDS and Behavior
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    ABSTRACT: Background: The epidemiology of sports-related concussion is not well-described in the literature. This paper presents a descriptive epidemiology of concussion in seven high school and collegiate sports. Methods: We used the data from Concussion Prevention Initiative (CPI), which enrolled 8905 athletes at 210 high schools and 26 colleges in a prospective cohort study of 7 sports (football, men’s and women’s soccer, men’s and women’s lacrosse, and men’s and women’s ice hockey) between 1999 and 2001. Injury risks and injury rates were used to characterize the incidence of concussion, and changes in symptoms over time were described. Results: A total of 375 concussions were observed. The incidence of concussion was highest in football, followed by women’s lacrosse, men’s lacrosse, men’s soccer, and women’s soccer (only 10 ice hockey teams were included, too few to quantify incidence). The rate of incident concussion was strongly associated with history of concussion in the previous 24 months (rate ratio = 5.5; 95 %CI: 3.9, 7.8, for 2 or more concussions relative to no previous concussion). The most common symptoms at time of injury were headache (87 %), balance problems/dizziness (77 %), and feeling “in a fog” (62 %). Loss of consciousness and amnesia were present in relatively few cases (9 and 30 %). The most common mechanism of injury was collision with another player. Conclusions: Sports-related concussions present with a diverse range of symptoms and are associated with previous concussion history.
    Full-text · Article · Jun 2015
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    Thomas P Dompier · Stephen W Marshall · Zachary Y Kerr · Ross Hayden

    Full-text · Article · Jun 2015 · Journal of athletic training
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    ABSTRACT: A report by the Institute of Medicine called for comprehensive nationwide concussion incidence data across the spectrum of athletes aged 5 to 23 years. To describe the incidence of concussion in athletes participating in youth, high school, and collegiate American football. Data were collected by athletic trainers at youth, high school, and collegiate football practices and games to create multiple prospective observational cohorts during the 2012 and 2013 football seasons. Data were collected from July 1, 2012, through January 31, 2013, for the 2012 season and from July 1, 2013, through January 31, 2014, for the 2013 season. The Youth Football Surveillance System included 118 youth football teams, providing 4092 athlete-seasons. The National Athletic Treatment, Injury and Outcomes Network program included 96 secondary school football programs, providing 11 957 athlete-seasons. The National Collegiate Athletic Association Injury Surveillance Program included 24 member institutions, providing 4305 athlete-seasons. All injuries regardless of severity, including concussions, and athlete exposure information were documented by athletic trainers during practices and games. Injury rates, injury rate ratios, risks, risk ratios, and 95% CIs were calculated. Concussions comprised 9.6%, 4.0%, and 8.0% of all injuries reported in the Youth Football Surveillance System; National Athletic Treatment, Injury and Outcomes Network; and National Collegiate Athletic Association Injury Surveillance Program, respectively. The game concussion rate was higher than the practice concussion rate across all 3 competitive levels. The game concussion rate for college athletes (3.74 per 1000 athlete exposures) was higher than those for high school athletes (injury rate ratio, 1.86; 95% CI, 1.50-2.31) and youth athletes (injury rate ratio, 1.57; 95% CI, 1.17-2.10). The practice concussion rate in college (0.53 per 1000 athlete exposures) was lower than that in high school (injury rate ratio, 0.80; 95% CI, 0.67-0.96). Youth football had the lowest 1-season concussion risks in 2012 (3.53%) and 2013 (3.13%). The 1-season concussion risk was highest in high school (9.98%) and college (5.54%) in 2012. Football practices were a major source of concussion at all 3 levels of competition. Concussions during practice might be mitigated and should prompt an evaluation of technique and head impact exposure. Although it is more difficult to change the intensity or conditions of a game, many strategies can be used during practice to limit player-to-player contact and other potentially injurious behaviors.
    Full-text · Article · May 2015
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    ABSTRACT: To examine statewide emergency department (ED) visit data for motorcycle crash morbidity and healthcare utilization due to traumatic brain injuries (TBIs) and non-TBIs. North Carolina ED data (2010-2012) and hospital discharge data (2009-2011). Statewide ED visits and hospitalizations due to injuries from traffic-related motorcycle crashes stratified by TBI status. Descriptive study. Descriptive statistics include age, sex, mode of transport, disposition, expected source of payment, hospital length of stay, and hospital charges. Over the study period, there were 18 780 ED visits and 3737 hospitalizations due to motorcycle crashes. Twelve percent of ED visits for motorcycle crashes and 26% of hospitalizations for motorcycle crashes had a diagnosis of TBI. Motorcycle crash-related hospitalizations with a TBI diagnosis had median hospital charges that were nearly $9000 greater than hospitalizations without a TBI diagnosis. Emergency department visits and hospitalizations due to motorcycle crashes with a TBI diagnosis consumed more healthcare resources than motorcycle crash-related ED visits and hospitalizations without a TBI diagnosis. Increased awareness of motorcyclists by other road users and increased use of motorcycle helmets are 2 strategies to mitigate the incidence and severity of motorcycle crash injuries, including TBIs.
    Full-text · Article · May 2015 · The Journal of head trauma rehabilitation
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    ABSTRACT: Overuse injuries result from microtrauma due to repetitive loading combined with insufficient tissue recovery time and can result in both immediate and long-term time loss from sports. Overuse injury rates and patterns differ across college and high school populations, sport, and sex. Descriptive epidemiology study. Surveillance data for 16 sports from the National Collegiate Athletic Association's Injury Surveillance System (NCAA ISS; 2004-2005 through 2008-2009) and 14 sports from High School Reporting Information Online (High School RIO; 2006-2007 through 2012-2013) were analyzed. All reported injuries had an injury mechanism of overuse/gradual onset (college) or overuse/chronic (high school). Overuse injury incidence rates were calculated, and rate ratios with 95% CIs were used to compare subgroups. The rate of overuse injury was 3.28 times higher in college than high school sports (95% CI, 3.12-3.44). The rate of overuse injury among sex-comparable sports was higher in female than male athletes in both populations (college rate ratio, 1.25; 95% CI, 1.16-1.35; high school rate ratio, 1.55; 95% CI, 1.43-1.68). The lower extremity was the most commonly injured body site (college, 69.4%; high school, 70.4%). A larger proportion of overuse injuries among college athletes resulted in time loss of more than 21 days (college, 20.4%; high school, 7.7%) and surgery (college, 5.2%, high school, 2.5%). Overuse injuries can impose a significant burden on college and high school athletes. Interventions addressing prevention of overuse injury are needed. © 2015 The Author(s).
    No preview · Article · Apr 2015 · The American Journal of Sports Medicine
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    ABSTRACT: We evaluated how attention deficit-hyperactivity disorder (ADHD) and learning disability (LD) are associated with concussion history and performance on standard concussion assessment measures. Based on previous reports that developmental disorders are associated with increased injury proneness and poorer cognitive performance, we anticipated that ADHD and LD would be associated with increased history of concussion and poorer baseline performance on assessment measures. Cross-sectional study. Clinical research center. The study sample aggregated data from two separate projects: the National Collegiate Athletic Association Concussion Study and Project Sideline. We analyzed preseason baseline data from 8056 high school and collegiate athletes (predominantly male football players) enrolled in prior studies of sport-related concussion. Measures included demographic/health history, symptoms, and cognitive performance. Attention deficit-hyperactivity disorder and LD were associated with 2.93 and 2.08 times the prevalence, respectively, of 3+ historical concussions (for comorbid ADHD/LD the prevalence ratio was 3.38). In players without histories of concussion, individuals with ADHD reported more baseline symptoms, and ADHD and LD were associated with poorer performance on baseline cognitive tests. Interactive effects were present between ADHD/LD status and concussion history for self-reported symptoms. Neurodevelopmental disorders and concussion history should be jointly considered in evaluating concussed players. Clinical judgments of self-reported symptoms and cognitive performance should be adjusted based on athletes' individual preinjury baselines or comparison with appropriate normative samples.
    No preview · Article · Apr 2015 · Clinical journal of sport medicine: official journal of the Canadian Academy of Sport Medicine
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    ABSTRACT: Background: Activity-related patient-reported outcome measures are an important component of assessment after knee ligament injury in young and physically active patients; however, normative data for most activity scales are limited. Objective: To present reference values by sex for the Marx Activity Rating Scale (MARS) within a young and physically active population while accounting for knee ligament injury history and sex. Study Design: Cross-sectional study. Level of Evidence: Level 2. Methods: All incoming freshman entering a US Service Academy in June of 2011 were recruited to participate in this study. MARS was administered to 1169 incoming freshmen (203 women) who consented to participate within the first week of matriculation. All subjects were deemed healthy and medically fit for military service on admission. Subjects also completed a baseline questionnaire that asked for basic demographic information and injury history. We calculated means with standard deviations, medians with interquartile ranges, and percentiles for ordinal and continuous variables, and frequencies and proportions for dichotomous variables. We also compared median scores by sex and history of knee ligament injury using the Kruskal-Wallis test. MARS was the primary outcome of interest. Results: The median MARS score was significantly higher for men when compared with women (χ2 = 13.22, df = 1, P < 0.001) with no prior history of knee ligament injury. In contrast, there was no significant difference in median MARS scores between men and women (χ2 = 0.47, df = 1, P = 0.493) who reported a history of injury. Overall, median MARS scores were significantly higher among those who reported a history of knee ligament injury when compared with those who did not (χ2 = 9.06, df = 1, P = 0.003). Conclusion: Assessing activity as a patient-reported outcome after knee ligament injury is important, and reference values for these instruments need to account for the influence of prior injury and sex.
    No preview · Article · Mar 2015 · Sports Health A Multidisciplinary Approach
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    ABSTRACT: Objective: The study described initial pharmacological treatment of children in the United Kingdom diagnosed as having ADHD and assessed predictors of medication persistence. Methods: U.K. children ages 3-16 diagnosed as having ADHD between 1994 and 2006 were identified from primary care practice data. Child characteristics, prescription patterns, and initial medication prescribed were described over the study period. The associations of child and clinical factors with medication persistence (defined as initial treatment length greater than six months) were estimated by using binomial regression. Results: Of 2,878 children with an ADHD diagnosis, 46% (N=1,314) received at least one prescription for ADHD medication within two years of diagnosis. The mean initial treatment length was 10.7±.5 months. Only 35% (N=464) of pharmacologically treated children had a treatment length greater than six months after initial medication prescription when the analysis used a 30-day grace period; 57% were persistent in treatment when a less stringent 60-day grace period was used. Children who were initially prescribed long-acting methylphenidate were more likely to persist in treatment than those prescribed standard methylphenidate (risk ratio=1.2, 95% confidence interval=1.1-1.4). Conclusions: A large proportion of children who received medication for ADHD in primary care did not continue in initial treatment for more than six months. Few child or clinical factors were associated with treatment persistence. Epidemiological research about the effects of long-term ADHD medication use should account for the observed limited persistence in medication treatment.
    No preview · Article · Mar 2015 · Psychiatric services (Washington, D.C.)
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    ABSTRACT: BACKGROUND North Carolina requires motorcyclists of all ages to wear federally approved safety helmets. The purpose of this article is to estimate the impact of this state law in terms of hospital admissions for traumatic brain injury (TBI) and associated hospital charges. METHODS Hospital admissions of North Carolina motorcyclists with TBIs and associated hospital charges in 2011 were extracted from the North Carolina Hospital Discharge Data system. We estimated hospital admissions and charges for the same year under the counterfactual condition of North Carolina without a universal motorcycle helmet law by using various substitutes (Florida, Pennsylvania, and South Carolina residents treated in North Carolina). RESULTS North Carolina's universal helmet law prevented an estimated 190 to 226 hospital admissions of North Carolina motorcyclists with TBI in 2011. Averted hospital charges to taxpayer-funded sources (ie, government and public charges) were estimated to be between $9.5 million and $11.6 million for 2011, and total averted hospital charges for 2011 were estimated to be between $25.3 million and $31.0 million. LIMITATIONS Cost estimates are limited to inpatients during the initial period of hospital care. This study was unable to capture long-term health care costs and productivity losses incurred by North Carolina's TBI patients and their caregivers. CONCLUSIONS North Carolina's universal motorcycle helmet law generates health and economic benefits for the state and its taxpayers.
    Full-text · Article · Mar 2015 · North Carolina medical journal

Publication Stats

10k Citations
1,046.37 Total Impact Points


  • 1996-2016
    • University of North Carolina at Chapel Hill
      • • Department of Epidemiology
      • • Department of Exercise and Sport Science
      • • Injury Prevention Research Center
      North Carolina, United States
  • 2013
    • United States Military Academy West Point
      ვესტ-პოინტი, New York, United States
  • 2008
    • University of North Carolina at Charlotte
      Charlotte, North Carolina, United States
    • Iowa State University
      • Department of Industrial and Manufacturing Systems Engineering
      Ames, Iowa, United States
  • 2007
    • Indiana University Bloomington
      Bloomington, Indiana, United States
  • 2006
    • University of Minnesota Duluth
      Duluth, Minnesota, United States
  • 2003
    • Boston University
      Boston, Massachusetts, United States
  • 1992-1995
    • University of Otago
      • Injury Prevention Research Unit
      Taieri, Otago, New Zealand