Team-Level Predictors of Football Injuries in Fifty North Carolina High Schools
Creators: name: Chelminski, Paul Roman, M.D.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2003

description: Background: There is a growing recognition that sports and recreational injuries constitute an important public health problem. They account for more emergency department visits than motor vehicle collisions. The preponderance of these injuries occur in the mid-adolescent years. A dearth of prospective epidemiologic information on sport injury has hampered the development of population-based interventions to prevent sports injury. Risk factors for injury are poorly understood, and most preventive interventions are empirical. To identify potential risk factors for football injury, this analysis examines injuries in a cohort of fifty North Carolina high school varsity teams. It hypothesizes that certain team-level characteristics are systematically related to variation in injury rates. Methods: The North Carolina High School Athletic Injury Study (NCHSAIS) surveyed sports injuries in approximately one hundred North Carolina high schools between 1996 and 1999. Twelve girls and boys varsity sports were studied, and each school surveyed six sports. Injuries were expressed as a rate, defined as the number of injuries per 10[5] athlete-exposures, an exposure being a practice or a game. To accommodate the team as the unit of analysis in our study, injury rates were expressed as the number of injuries per 10[5] team-exposures. Univariate statistics are reported as means and proportions. In bivaviate analyses, the team injury rate is the continuous dependant variable and the primary outcome of interest. Small sample size and a limited number of team-level variables precluded comprehensive multivariate modeling. Results: The average injury rate was 411 per 10[5] exposures among the 50 schools surveying football injuries. The game injury rate, 1566 10[5] exposures, was nine times higher than the practice injury rate, 175 per 10[5] exposures (p<0.001). Football coaches had an average of 20 years of experience. Almost all coaches had taken a coaching class and most were certified in cardiopulmonary resuscitation and first aid. There was substantial variation in team injury rates. Inter-quartile injury rates varied by a factor of more than four. The injury rate in the first quartile rate was 169 per 10[5] exposures, while in the fourth quartile the rate was 739 per 10[5] exposures. In bivariate analyses, team size and first aid training of coaches correlated with injury rates. Smaller teams had significantly more injuries than larger teams (p=0.0026). The effect of team size in injury rates was very strong in games. Adjusting for the tendency of smaller schools to have smaller teams, the model predicted 420 fewer game injuries per 10[5] exposures for every additional 10 players (p=0.0036). Thirty-three percent of coaches in the highest injury quartile did not have a history of first aid training (p=0.0011). Conclusion: Substantial variation exists in injury rates among football teams. Injuries occur much more frequently in games than practices. Team size and first aid training of coaches are predictors of football injuries and may explain some of the variation seen in team rates. Smaller teams have a higher burden of injury than larger teams. Teams with high injury rates are more likely to have coaches without a history of first aid training. These findings suggest strategies for prevention such as insuring adequate team size and promoting the certification of all coaches in first aid. Future research should try to define those factors that make games especially hazardous.