The Football Players' Health Study at Harvard University: Design and objectives.

The Football Players Health Study at Harvard University (FPHS) is a unique transdisciplinary, strategic initiative addressing the challenges of former players' health after having participated in American style football (ASF). The whole player focused FPHS is designed to deepen understanding of the benefits and risks of participation in ASF, identify risks that are potentially reversible or preventable, and develop interventions or approaches to improve the health and wellbeing of former players. We are recruiting and following a cohort of former professional ASF players who played since 1960 (current n = 3785). At baseline, participants complete a self-administered standardized questionnaire, including initial reporting of exposure history and physician-diagnosed health conditions. Additional arms of the initiative are addressing targeted studies, including promising primary, secondary, and tertiary interventions; extensive in-person clinical phenotyping, and legal and ethical concerns of the play. This paper describes the components of the FPHS studies undertaken and completed thus far, as well as those studies currently underway or planned for the near future. We present our initiatives herein as a potential paradigm of one way to proceed (acknowledging that it is not the only way). We share what we have learned so that it may be useful to others, particularly in regard to trying to make professional sports meet the needs of multiple stakeholders ranging from players to owners, to fans, and possibly even to parents making decisions for their children.

The impact of weather, road surface, time-of-day, and light conditions on severity of bicycle-motor vehicle crash injuries.

BACKGROUND: This study examined whether environmental variables including weather, road surface, time-of-day, and light conditions were associated with the severity of injuries resulting from bicycle-motor vehicle crashes. METHODS: Using log-binomial regressions, we analyzed 113 470 police reports collected between 2000 and 2014 in four U.S. states with environmental and injury severity information. "Severe" injuries included fatal and incapacitating injuries, and "non-severe" included non-incapacitating, possible or no-injuries. RESULTS: Light condition was significantly associated with the injury severity to the bicyclist with more severe injuries at dawn (RR = 1.62 [95%CI 1.35-1.94]) and during darkness (both lighted and unlighted roads: 1.32 [1.24-1.40], respectively, 1.57 [1.41-1.76]) as compared to daylight. In these conditions of low visibility, risk was further increased during early morning hours before 7 am (1.61 [1.22-2.13]). CONCLUSIONS: Crashes in low light conditions and during early morning hours are more likely to result in higher injury severity.

The role of intersection and street design on severity of bicycle-motor vehicle crashes.

BACKGROUND: Safety concerns are a major barrier to cycling. Intersection and street design variables such as intersection angles and street width might contribute to the severity of crashes and the safety concerns. In this study we examined whether these design variables were associated with bicycle-motor vehicle crashes (BMVC) severity. METHODS: Using the geographical information system and latitudes/longitudes recorded by the police using a global positioning device, we extracted intersection angles, street width, bicycle facilities, posted speed limits and annual average daily traffic from 3266 BMVC data from New York City police records. Additional variables about BMVC, including age and sex of the bicyclist, time of the day, road surface conditions, road character, vehicle type and injury severity, were obtained from police reports. Injury severity was classified as severe (incapacitating or killed) or non-severe (non-incapacitating, possible injury). The associations between injury severity and environment design variables were examined using multivariate log-binomial regression model. FINDINGS: Compared with crashes at orthogonal intersections, crashes at non-orthogonal intersections had 1.37 times (95% CI 1.05 to 1.80) and non-intersection street segments had 1.31 times (95% CI 1.01 to 1.70) higher risk of a severe injury. Crashes that involved a truck or a bus were twice as likely to result in a severe injury outcome; street width was not significantly associated with injury severity. CONCLUSION: Crashes at non-orthogonal intersections and non-intersection segments are more likely to result in higher injury severity. The findings can be used to improve road design and develop effective safety interventions.

A structural equation modelling approach examining the pathways between safety climate, behaviour performance and workplace slipping.

OBJECTIVE: Safety climate has previously been associated with increasing safe workplace behaviours and decreasing occupational injuries. This study seeks to understand the structural relationship between employees' perceptions of safety climate, performing a safety behaviour (ie, wearing slip-resistant shoes) and risk of slipping in the setting of limited-service restaurants. METHODS: At baseline, we surveyed 349 employees at 30 restaurants for their perceptions of their safety training and management commitment to safety as well as demographic data. Safety performance was identified as wearing slip-resistant shoes, as measured by direct observation by the study team. We then prospectively collected participants' hours worked and number of slips weekly for the next 12 weeks. Using a confirmatory factor analysis, we modelled safety climate as a higher order factor composed of previously identified training and management commitment factors. RESULTS: The 349 study participants experienced 1075 slips during the 12-week follow-up. Confirmatory factor analysis supported modelling safety climate as a higher order factor composed of safety training and management commitment. In a structural equation model, safety climate indirectly affected prospective risk of slipping through safety performance, but no direct relationship between safety climate and slips was evident. CONCLUSIONS: Results suggest that safety climate can reduce workplace slips through performance of a safety behaviour as well as suggesting a potential causal mechanism through which safety climate can reduce workplace injuries. Safety climate can be modelled as a higher order factor composed of safety training and management commitment.

Editorial: emerging issues in sociotechnical systems thinking and workplace safety.

The burden of on-the-job accidents and fatalities and the harm of associated human suffering continue to present an important challenge for safety researchers and practitioners. While significant improvements have been achieved in recent decades, the workplace accident rate remains unacceptably high. This has spurred interest in the development of novel research approaches, with particular interest in the systemic influences of social/organisational and technological factors. In response, the Hopkinton Conference on Sociotechnical Systems and Safety was organised to assess the current state of knowledge in the area and to identify research priorities. Over the course of several months prior to the conference, leading international experts drafted collaborative, state-of-the-art reviews covering various aspects of sociotechnical systems and safety. These papers, presented in this special issue, cover topics ranging from the identification of key concepts and definitions to sociotechnical characteristics of safe and unsafe organisations. This paper provides an overview of the conference and introduces key themes and topics. PRACTITIONER SUMMARY: Sociotechnical approaches to workplace safety are intended to draw practitioners' attention to the critical influence that systemic social/organisational and technological factors exert on safety-relevant outcomes. This paper introduces major themes addressed in the Hopkinton Conference within the context of current workplace safety research and practice challenges.

Sociotechnical approaches to workplace safety: Research needs and opportunities.

The sociotechnical systems perspective offers intriguing and potentially valuable insights into problems associated with workplace safety. While formal sociotechnical systems thinking originated in the 1950s, its application to the analysis and design of sustainable, safe working environments has not been fully developed. To that end, a Hopkinton Conference was organised to review and summarise the state of knowledge in the area and to identify research priorities. A group of 26 international experts produced collaborative articles for this special issue of Ergonomics, and each focused on examining a key conceptual, methodological and/or theoretical issue associated with sociotechnical systems and safety. In this concluding paper, we describe the major conference themes and recommendations. These are organised into six topic areas: (1) Concepts, definitions and frameworks, (2) defining research methodologies, (3) modelling and simulation, (4) communications and decision-making, (5) sociotechnical attributes of safe and unsafe systems and (6) potential future research directions for sociotechnical systems research. PRACTITIONER SUMMARY: Sociotechnical complexity, a characteristic of many contemporary work environments, presents potential safety risks that traditional approaches to workplace safety may not adequately address. In this paper, we summarise the investigations of a group of international researchers into questions associated with the application of sociotechnical systems thinking to improve worker safety.

Duration of slip-resistant shoe usage and the rate of slipping in limited-service restaurants: results from a prospective and crossover study.

Several studies have indicated that slip-resistant shoes may have a positive effect on reducing the risk of slips and falls, a leading cause of injury at work. Few studies, however, have examined how duration of shoe usage affects their slip-resistance properties. This study examined the association between the duration of slip-resistant shoes usage and the self-reported rate of slipping in limited-service restaurant workers. A total of 475 workers from 36 limited-service restaurants in the USA were recruited to participate in a 12-week prospective study of workplace slipping. Of the 475 participants, 83 reported changing to a new pair of shoes at least once during the 12-week follow-up. The results show that slip-resistant shoes worn for less than six months were moderately more effective than those worn for more than six months. Changing to a new pair of shoes among those wearing slip-resistant shoes at baseline was associated with a 55% reduction in the rate of slipping (RR = 0.45, 95% CI = 0.23-0.89). Further research is needed to develop criteria for the replacement of slip-resistant shoes.

Perception of slipperiness and prospective risk of slipping at work.

OBJECTIVES: Falls are a leading cause of injury at work, and slipping is the predominant cause of falling. Prior research has suggested a modest correlation between objective measures (such as coefficient of friction, COF) and subjective measures of slipperiness (such as worker perceptions) in the workplace. However, the degree of association between subjective measures and the actual risk of slipping at the workplace is unknown. This study examined the association between perception of slipperiness and the risk of slipping. METHODS: 475 workers from 36 limited-service restaurants participated in a 12-week prospective cohort study. At baseline, demographic information was collected, participants rated floor slipperiness in eight areas of the restaurant, and work environment factors, such as COF, were measured. Restaurant-level and area-level mean perceptions of slipperiness were calculated. Participants then reported their slip experience at work on a weekly basis for the next 12 weeks. The associations between perception of slipperiness and the rate of slipping were assessed. RESULTS: Adjusting for age, gender, body mass index, education, primary language, mean COF, use of slip-resistant shoes, and restaurant chain, each 1-point increase in mean restaurant-level perception of slipperiness (4-point scale) was associated with a 2.71 times increase in the rate of slipping (95% CI 1.25 to 5.87). Results were similar for area-level perception within the restaurant (rate ratios (RR) 2.92, 95% CI 2.41 to 3.54). CONCLUSIONS: Perceptions of slipperiness and the subsequent rate of slipping were strongly associated. These findings suggest that safety professionals, risk managers and employers could use aggregated worker perceptions of slipperiness to identify slipping hazards and, potentially, to assess intervention effectiveness.

Factors associated with use of slip-resistant shoes in US limited-service restaurant workers.

OBJECTIVES: Slips and falls are a leading cause of injury at work. Several studies have indicated that slip-resistant shoes can reduce the risk of occupational slips and falls. Few studies, however, have examined the determinants of slip-resistant shoe use. This study examined the individual and workplace factors associated with slip-resistant shoe use. METHODS: 475 workers from 36 limited-service restaurants in the USA participated in a study of workplace slipping. Demographic and job characteristic information about each participant was collected. Restaurant managers provided information on whether slip-resistant shoes were provided and paid for by the employer and whether any guidance was given regarding slip-resistant shoe use when they were not provided. Kitchen floor coefficient of friction was measured. Slip-resistant status of the shoes was determined by noting the presence of a 'slip-resistant' marking on the sole. Poisson regression with robust SE was used to calculate prevalence ratios. RESULTS: 320 participants wore slip-resistant shoes (67%). In the multivariate analysis, the prevalence of slip-resistant shoe use was lowest in 15-19-year age group. Women were more likely to wear slip-resistant shoes (prevalence ratio 1.18, 95% CI 1.07 to 1.31). The prevalence of slip-resistant shoe use was lower when no guidance regarding slip-resistant shoes was given as compared to when they were provided by the employer (prevalence ratio 0.66, 95% CI 0.55 to 0.79). Education level, job tenure and the mean coefficient of friction had no significant effects on the use of slip-resistant shoes. CONCLUSION: Provision of slip-resistant shoes was the strongest predictor of their use. Given their effectiveness and low cost, employers should consider providing slip-resistant shoes at work.

The utility of a safety climate scale among workers with a work-related permanent impairment who have returned to work.

BACKGROUND: Safety climate (SC) is a robust leading indicator of occupational safety outcomes. There is, however, limited research on SC among workers who have returned to work with a work-related permanent impairment. OBJECTIVE: This study examined three propositions: (1) a two-level model of SC (group-level and organization-level SC) will provide the best fit to the data; (2) antecedent factors such as safety training, job demands, supervisor support, coworker support, and decision latitude will predict SC; and (3) previously reported associations between SC and outcomes such as reinjury, work-family conflict, job performance, and job security will be observed. METHOD: A representative cross-sectional survey gathered information about experiences during the first year of work reintegration. About one year after claim closure, 599 interviews with workers were conducted (53.8% response rate). Confirmatory factor analyses were conducted to test the factor structure of the SC construct. Further, researchers used correlation analyses to examine the criterion-related validity. RESULTS: Consistent with general worker populations, our findings suggest the following: (1) the two-factor structure of SC outperformed the single-factor structure in our population of workers with a permanent impairment; (2) correlations demonstrate that workplace safety training, decision latitude, supervisor support, coworker support, and job demands could predict SC; and (3) SC may positively impact reinjury risk, work-family conflict, and may increase job performance and job security. CONCLUSIONS: Our study validated a two-factor SC scale among workers with a history of disabling workplace injury or permanent impairment who have returned to work. Practical applications of this scale will equip organizations with the necessary data to improve working conditions for this population.

A prospective study of floor surface, shoes, floor cleaning and slipping in US limited-service restaurant workers.

OBJECTIVES: Slips and falls are a leading cause of injury at work. Few studies, however, have systematically examined risk factors of slipping outside the laboratory environment. This study examined the association between floor surface characteristics, slip-resistant shoes, floor cleaning frequency and the risk of slipping in limited-service restaurant workers. METHODS: 475 workers from 36 limited-service restaurants from three major chains in six states in the USA were recruited to participate in a prospective cohort study of workplace slipping. Kitchen floor surface roughness and coefficient of friction (COF) were measured in eight working areas and then averaged within each restaurant. The use of slip-resistant shoes was determined by examining the participant's shoes and noting the presence of a 'slip-resistant' marking on the sole. Restaurant managers reported the frequency of daily kitchen floor cleaning. Participants reported their slip experience and work hours weekly for up to 12 weeks. The survey materials were made available in three languages: English, Spanish and Portuguese. The associations between rate of slipping and risk factors were assessed using a multivariable negative binomial generalised estimating equation model. RESULTS: The mean of individual slipping rate varied among the restaurants from 0.02 to 2.49 slips per 40 work hours. After adjusting for age, gender, BMI, education, primary language, job tenure and restaurant chain, the use of slip-resistant shoes was associated with a 54% reduction in the reported rate of slipping (95% CI 37% to 64%), and the rate of slipping decreased by 21% (95% CI 5% to 34%) for each 0.1 increase in the mean kitchen COF. Increasing floor cleaning frequency was significantly associated with a decreasing rate of slipping when considered in isolation but not after statistical adjustment for other factors. CONCLUSION: These results provide support for the use of slip-resistant shoes and measures to increase COF as preventive interventions to reduce slips, falls and injuries.

Rushing, distraction, walking on contaminated floors and risk of slipping in limited-service restaurants: a case--crossover study.

OBJECTIVES: This nested case-crossover study examined the association between rushing, distraction and walking on a contaminated floor and the rate of slipping, and whether the effects varied according to weekly hours worked, job tenure and use of slip-resistant shoes. METHODS: At baseline, workers from 30 limited-service restaurants in the USA reported average work hours, average weekly duration of exposure to each transient risk factor and job tenure at the current location. Use of slip-resistant shoes was determined. During the following 12 weeks, participants reported weekly their slip experience and exposures to the three transient exposures at the time of slipping. The case-crossover design was used to estimate the rate ratios using the Mantel-Haenszel estimator for person-time data. RESULTS: Among 396 participants providing baseline information, 210 reported one or more slips with a total of 989 slips. Rate of slipping was 2.9 times higher when rushing as compared to working at a normal pace (95% CI 2.5 to 3.3). Rate of slipping was also significantly increased by distraction (rate ratio (RR) 1.7, 95% CI 1.5 to 2.0) and walking on a contaminated floor (RR 14.6, 95% CI 12.6 to 17.0). Use of slip-resistant shoes decreased the effects of rushing and walking on a contaminated floor. Rate ratios for all three transient factors decreased monotonically as job tenure increased. CONCLUSION: The results suggest the importance of these transient risk factors, particularly floor contamination, on rate of slipping in limited-service restaurant workers. Stable characteristics, such as slip-resistant shoes, reduced the effects of transient exposures.

Factors associated with worker slipping in limited-service restaurants.

OBJECTIVE: Slips, trips and falls (STF) are responsible for a substantial injury burden in the global workplace. Restaurant environments are challenged by STF. This study assessed individual and work environment factors related to slipping in US limited-service restaurant workers. METHODS: Workers in 10 limited-service restaurants in Massachusetts were recruited to participate. Workers' occupational slip and/or fall history within the past 4 weeks was collected by multilingual written questionnaires. Age, gender, job tenure, work hours per week and work shift were also collected. Shoe type, condition and gross shoe contamination were visually assessed. Floor friction was measured and each restaurant's overall mean coefficient of friction (COF) was calculated. The logistic generalised estimating equations model was used to compute adjusted odds ratios (OR). RESULTS: Of 125 workers, 42 reported one or more slips in the past 4 weeks with two reporting a resultant fall. Results from multivariable regression showed that higher restaurant mean COF was significantly associated with a decreased risk of self-reported slipping (OR 0.59, 95% CI 0.42 to 0.82). From the highest to the lowest COF restaurant, the odds of a positive slip history increased by a factor of more than seven. Younger age, male gender, lower weekly work hours and the presence of gross contamination on worker's shoe sole were also associated with increased odds of slip history. CONCLUSION: Published findings of an association between friction and slipping and falling in actual work environments are rare. The findings suggest that effective intervention strategies to reduce the risk of slips and falls in restaurant workers could include increasing COF and improving housekeeping practices.

Patterns of work-related traumatic hand injury among hospitalised workers in the People's Republic of China.

OBJECTIVES: This study describes the type, location and severity of work-related acute traumatic hand injuries of 560 workers treated in 11 hospitals in three economically active cities in the People's Republic of China (PRC) over a 2-year period. METHODS: A structured questionnaire was used to collect participant's information. Log-linear and logistic models were constructed to identify factors associated with injury occurrence and severity, respectively. RESULTS: Participants (n=560) had a mean age of 31.7 years (SD 10.5), 74.4% were men. 85.4% of participants were employed in manufacturing industries; 51.7% of 750 injuries were to the left hand. The index finger was injured most often and the most severe injury occurred to the right thumb. 68.3% of participants had only a single type of injury (29.7% crushes, 25.7% amputations and 18.5% fractures). Severe injuries occurred most often while working with food products (79.2% severe), furniture (72.2%), non-metallic mineral products (71.4%) and wood products (70.6%). Powered machines were involved in 59.5% of injuries. Injury frequency was associated with gender (male vs female, odds ratio (OR) 2.9, 95% CI 2.4 to 3.5) and company size (100 employees, OR 2.5, 95% CI 2.1 to 3.1). Injury severity was associated with gender (male vs female OR 0.6, 95% CI 0.4 to 0.9) and powered machine use (OR 2.2, 95% CI 1.3 to 3.7). CONCLUSIONS: The present study suggests that working in manufacturing industries and working with powered machines are the primary sources of severe hand injuries in hospitalised workers in economically active areas of the PRC.

Workers' experience of slipping in U.S. limited-service restaurants.

The leading cause of injuries among restaurant workers is same-level falls, a significant proportion of which result from slipping. This study examines the experience of limited-service restaurant workers with slipping, their use of slip-resistant shoes, and their floor-cleaning practices. A total of 475 workers from 36 limited-service restaurants in six U.S. states participated in a 12-week prospective cohort study on slipping in the workplace. At baseline, participants completed a survey that gathered information about their demographics, perceptions of floor slipperiness, use of slip-resistant shoes, floor cleaning practices, and number of slips experienced in the previous 4 weeks. During the subsequent 12 weeks, participants reported their slip experience weekly. Restaurant managers reported kitchen floor cleaning protocols and shoe policies. The overall rate of slipping during the 12 weeks of the prospective study was 0.44 slips per 40 work hours. The mean of the individual rate of slipping varied among the restaurants from 0.02 to 2.49 slips per 40 work hours, a rate ratio of more than 100 among the restaurants with the highest and the lowest rate of slipping. Such a large variation, which is unlikely due to chance alone (p < 0.05), suggests that some restaurants are better able to control slipping than others. The highest numbers of slips were reported in the sink and fryer areas, which were also identified by restaurant workers as being the most slippery. Liquid and grease were reported as floor contaminants in over 70% of the slips. In restaurants where slip-resistant shoes were provided by the employer, 91% of participants wore them; whereas if they were neither provided nor encouraged, only 53.5% wore them (p < 0.01). Use of enzyme-based floor cleaners was widespread (25/36). In these restaurants, however, 62% of the participants who were responsible for cleaning floors reported using hot/warm water, thus violating the manufacturer's cold water floor cleaning protocol. These findings suggest that focused prevention efforts based on practices from restaurants with low rates of slipping could decrease slipping hazards.

Self-Reported Cognitive Function and Mental Health Diagnoses among Former Professional American-Style Football Players.

Clinical practice strongly relies on patients' self-report. Former professional American-style football players are hesitant to seek help for mental health problems, but may be more willing to report cognitive symptoms. We sought to assess the association between cognitive symptoms and diagnosed mental health problems and quality of life among a cohort of former professional players. In a cross-sectional design, we assessed self-reported cognitive function using items from the Quality of Life in Neurological Disorders (Neuro-QOL) Item Bank. We then compared mental health diagnoses and quality of life, assessed by items from the Patient-Reported Outcome Measurement Information System (PROMIS®), between former professional players reporting daily problems in cognitive function and former players not reporting daily cognitive problems. Of the 3758 former professional players included in the analysis, 40.0% reported daily problems due to cognitive dysfunction. Former players who reported daily cognitive problems were more likely to also report depression (18.0% vs. 3.3%, odds ratio [OR] = 6.42, 95% confidence interval [CI] [4.90-8.40]) and anxiety (19.1% vs. 4.3%, OR = 5.29, 95% CI [4.14-6.75]) than those without daily cognitive problems. Further, former players reporting daily cognitive problems were more likely to report memory loss and attention deficit(/hyperactivity) disorder and poorer general mental health, lower quality of life, less satisfaction with social activities and relationships, and more emotional problems. These findings highlight the potential of an assessment of cognitive symptoms for identifying former players with mental health, social, and emotional problems.

Work-related fatalities in the People's Republic of China.

Over the past several decades, work-related fatal incident reporting in China has become faster, more publicly accessible and, hence, a potentially more valuable process in support of the decision-making and enforcement actions of the government and safety professionals. A study was conducted to examine the characteristics of work-related fatalities in the People's Republic of China (PRC) available from the State Work Accident Briefing (SWAB) system. Injury incident records related to industries other than coal mining were downloaded from the SWAB system (April 2001 to March 2003). The findings were compared with a previously published regional work fatality study in China, data from the U.S. Census of Fatal Occupational Injuries, and estimates from the International Labor Organization (ILO). During the 2-year period, 1538 work-related events (7046 worker fatalities) were recorded. Collisions (25.6%), drownings (14.6%), and structural collapses (12.5%) were the most frequently reported fatal events. Collisions (24.5%) and falls (14.5%) were the most frequent causes of cited fatal events. Transportation (105.87 per 100 000); mining industries other than coal mining and quarrying (73.28); and electricity, gas, and water supply (14.88) were the industries with the highest estimated fatality rates. Generally, regions with lower economic activity reported more fatalities. The fatal injury rate estimated from the SWAB system was 4.80 per 100,000 (U.S. rate 4.00). ILO estimates for 1994 and 2002 were substantially higher than the estimates derived from the SWAB system. SWAB system differences with other data sources analyzed herein indicate that there remains room for system refinement.

Etiology of work-related electrical injuries: a narrative analysis of workers' compensation claims.

The purpose of this study was to provide new insight into the etiology of primarily nonfatal, work-related electrical injuries. We developed a multistage, case-selection algorithm to identify electrical-related injuries from workers' compensation claims and a customized coding taxonomy to identify pre-injury circumstances. Workers' compensation claims routinely collected over a 1-year period from a large U.S. insurance provider were used to identify electrical-related injuries using an algorithm that evaluated: coded injury cause information, nature of injury, "accident" description, and injury description narratives. Concurrently, a customized coding taxonomy for these narratives was developed to abstract the activity, source, initiating process, mechanism, vector, and voltage. Among the 586,567 reported claims during 2002, electrical-related injuries accounted for 1283 (0.22%) of nonfatal claims and 15 fatalities (1.2% of electrical). Most (72.3%) were male, average age of 36, working in services (33.4%), manufacturing (24.7%), retail trade (17.3%), and construction (7.2%). Body part(s) injured most often were the hands, fingers, or wrist (34.9%); multiple body parts/systems (25.0%); lower/upper arm; elbow; shoulder, and upper extremities (19.2%). The leading activities were conducting manual tasks (55.1%); working with machinery, appliances, or equipment; working with electrical wire; and operating powered or nonpowered hand tools. Primary injury sources were appliances and office equipment (24.4%); wires, cables/cords (18.0%); machines and other equipment (11.8%); fixtures, bulbs, and switches (10.4%); and lightning (4.3%). No vector was identified in 85% of cases. and the work process was initiated by others in less than 1% of cases. Injury narratives provide valuable information to overcome some of the limitations of precoded data, more specially for identifying additional injury cases and in supplementing traditional epidemiologic data for further understanding the etiology of work-related electrical injuries that may lead to further prevention opportunities.

Defining Exposures in Professional Football: Professional American-Style Football Players as an Occupational Cohort.

Studies of professional American football players have shown that football-related activities lead to acute injuries and may have long-term adverse health outcomes including osteoarthritis, neurocognitive impairment, and cardiovascular disease. However, the full complement of what constitutes professional football exposure has yet to be effectively articulated. Most likely, professional football exposure encompasses a multifaceted array of experiences including head impacts and joint stresses, long-term pain medication use, dietary restrictions, and strenuous training regimens. To study the health of professional American football players, characterizing the group as an occupational cohort and taking advantage of methods established within the discipline of occupational epidemiology may be beneficial. We conducted a narrative review of existing football research, occupational epidemiological methods papers, and occupational medicine studies. Here we describe the traditional occupational epidemiological approach to assessing exposure in a novel cohort and show how this framework could be implemented in studies of professional football players. In addition, we identify the specific challenges associated with studying an elite athletic occupational group, including the healthy worker effect and other types of selection and information biases, and explore these in the context of existing studies of football-related health. The application of well-established occupational epidemiological methods to professional football players may yield new insights into the effects of playing exposure and may provide opportunities for interventions to reduce harm.

Association of Concussion Symptoms With Testosterone Levels and Erectile Dysfunction in Former Professional US-Style Football Players.

Importance: Small studies suggest that head trauma in men may be associated with low testosterone levels and sexual dysfunction through mechanisms that likely include hypopituitarism secondary to ischemic injury and pituitary axonal tract damage. Athletes in contact sports may be at risk for pituitary insufficiencies or erectile dysfunction (ED) because of the high number of head traumas experienced during their careers. Whether multiple symptomatic concussive events are associated with later indicators of low testosterone levels and ED is unknown. Objective: To explore the associations between concussion symptom history and participant-reported indicators of low testosterone levels and ED. Design, Setting, and Participants: This cross-sectional study of former professional US-style football players was conducted in Boston, Massachusetts, from January 2015 to March 2017. Surveys on past football exposures, demographic factors, and current health conditions were sent via electronic and postal mail to participants within and outside of the United States. Analyses were conducted in Boston, Massachusetts; the data analysis began in March 2018 and additional analyses were performed through June 2019. Of the 13 720 male former players eligible to enroll who were contacted, 3506 (25.6%) responded. Exposures: Concussion symptom score was calculated by summing the frequency with which participants reported 10 symptoms, such as loss of consciousness, disorientation, nausea, memory problems, and dizziness, at the time of football-related head injury. Main Outcomes and Measures: Self-reported recommendations or prescriptions for low testosterone or ED medication served as indicators for testosterone insufficiency and ED. Results: In 3409 former players (mean [SD] age, 52.5 [14.1] years), the prevalence of indicators of low testosterone levels and ED was 18.3% and 22.7%, respectively. The odds of reporting low testosterone levels or ED indicators were elevated for previously established risk factors (eg, diabetes, sleep apnea, and mood disorders). Models adjusted for demographic characteristics, football exposures, and current health factors showed a significant monotonically increasing association of concussion symptom score with the odds of reporting the low testosterone indicator (highest vs lowest quartile, odds ratio, 2.39; 95% CI, 1.79-3.19; P < .001). The ED indicator showed a similar association (highest quartile vs lowest, odds ratio, 1.72; 95% CI, 1.30-2.27; P < .001). Conclusions and Relevance: Concussion symptoms at the time of injury among former football players were associated with current participant-reported low testosterone levels and ED indicators. These findings suggest that men with a history of head injury may benefit from discussions with their health care clinicians regarding testosterone deficiency and sexual dysfunction.