CUIRE

Injury Epidemiology

Injury is a public health issue for which the principles of prevention and control can be brought to bear. They are far from random events, and can be fitted to epidemiological models informing where and when they are likely to occur.

Much of my injury epidemiology work is related to pediatric pedestrian injuries in New York City.

This early article describes the epidemiology of pedestrian injuries in children and adolescents (ages <20) in an urban setting, and provides analyses of environmental and pedestrian variables. We obtained anonymous data for all motor vehicle crashes occurring in New York City over a 7-year period (1991-1997). Among 693,283 crashes, 97,245 resulted in injuries to 100,261 pedestrians of whom 32,578 were under age 20. Using census counts for the denominator, the overall incidence of pediatric pedestrian injuries was 246/100,000 per year, and the case fatality rate was 0.6%. Incidence rates peaked in the 6-14 year age group, and showed a modest annual decline during the study period. Younger children were more likely to be struck mid-block and during daylight hours, whereas adolescents were more likely to be struck at intersections and at night. For younger children, there was a sharp peak in incidence during the summer months. Road and weather conditions did not appear to affect injury risk.

In this
followup study, we investigated the hypothesis that relative to cars, light trucks and vans (including sports utility vehicles) are more likely to result in fatal pediatric pedestrian injury. We further hypothesized that this increased risk is a result of head injuries. The study sample consisted of 18,117 police records of motor vehicles involved in crashes in which one or more pedestrian aged 5 to 19 years old was injured or killed. We calculated frequencies and case fatality ratios for each vehicle body type and conducted a logistic regression analysis with light truck or van versus car as the exposure variable and fatal / non-fatal pedestrian injury as the outcome variable. After controlling for driver age, driver gender, vehicle weight, road surface condition and presence of head injury, 5 to 19 year-olds struck by light trucks or vans were more than twice as likely to die than those struck by cars (OR = 2.3 95% CI 1.4, 3.9). For the 5 to 9 year-old age group, light trucks and vans were four times as likely to be associated with fatal injury (OR = 4.2 95 % CI 1.9, 9.5). There was an association between head injury and light trucks and vans (OR=1.2, 95% CI 1.1, 1.3). We concluded that vehicle body type characteristics play an important role in pediatric pedestrian injury severity and may offer engineering-based opportunities for injury control.