title: Utility of a near real-time emergency department syndromic surveillance system to track injuries in New York City.
abstract: BACKGROUND
  The New York City emergency department (ED) syndromic surveillance (SS) system provides near real-time data on the majority of ED visits. The utility of ED SS for injury surveillance has not been thoroughly evaluated. We created injury syndromes based on ED chief complaint information and evaluated their utility compared to administrative billing data.
  
  
  METHODS
  Six injury syndromes were developed: traffic-related injuries to pedal cyclists, pedestrians, and motor vehicle occupants; fall-related injuries; firearm-related injuries; and assault-related stabbings. Daily injury counts were compared for ED SS and the administrative billing data for years 2008-2010. We examined characteristics of injury trends and patterns between the two systems, calculating descriptive statistics for temporal patterns and Pearson correlation coefficients (r) for temporal trends. We also calculated proportions of demographic and geospatial patterns for both systems.
  
  
  RESULTS
  Although daily volume of the injuries varied between the two systems, the temporal patterns were similar (all r values for daily volume exceeded 0.65). Comparisons of injuries by time of day, day of week, and quarter of year demonstrated high agreement between the two systems-the majority had an absolute percentage point difference of 2.0 or less. Distributions of injury by sex and age group also aligned well. Distribution of injury by neighborhood of residence showed mixed results-some neighborhood comparisons showed a high level of agreement between systems, while others were less successful.
  
  
  CONCLUSIONS
  As evidenced by the strong positive correlation coefficients and the small absolute percentage point differences in our comparisons, we conclude that ED SS captures temporal trends and patterns of injury-related ED visits effectively. The system could be used to identify changes in injury patterns, allowing for situational awareness during emergencies, timely response, and public messaging.
authors.affiliation: Bureau of Environmental Disease and Injury Prevention, NYC Department of Health and Mental Hygiene, New York, NY, USA. kacie.seil@gmail.com.|, 1100 West 49th Street, Room 704.11, Austin, TX, 78714, USA. kacie.seil@gmail.com.
authors.forename: Kacie
authors.initials: K
authors.lastname: Seil
authors.affiliation: Bureau of Environmental Disease and Injury Prevention, NYC Department of Health and Mental Hygiene, New York, NY, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Marcum
authors.affiliation: Bureau of Communicable Diseases, NYC Department of Health and Mental Hygiene, New York, NY, USA.
authors.forename: Ramona
authors.initials: R
authors.lastname: Lall
authors.affiliation: Bureau of Environmental Disease and Injury Prevention, NYC Department of Health and Mental Hygiene, New York, NY, USA.
authors.forename: Catherine
authors.initials: C
authors.lastname: Stayton
keywords: Emergency service, hospital; Epidemiology; Public health surveillance; Wounds and injuries