Counting Uncounted Gunshot Injuries: A Capture‐recapture Study Of People Minding Their Own Business

Objectives. To apply a novel statistical method to create a comprehensive estimate of incidence of firearm related injuries. Methods. A database of firearms injuries in New Haven, Connecticut, during a fivemonth period was created with records from law enforcement, emergency departments, emergency medical services (EMS), news media, and the medical examiner. The overlap of these various sources was operationalized in a capture-recapture model to generate an estimate of uncounted firearms injuries, and log linear modeling was used to control for positive and negative dependencies. Results. The combined data sources revealed 49 firearms injuries occurring during the study period within our defined geographical area. No single source recorded more than 43 of these injuries. Log-linear capture recapture methods estimated that the actual number of injuries was 49.7 (95% CI 49-52.3). Conclusions. No single source reaches complete case ascertainment for firearms injures. Combining multiple sources improves the estimate of injury incidence, but still results in an undercount. Log-linear capture-recapture methods can be used to improve the estimate of firearms injuries. Acknowledgements This work could not have been completed without the hard work of a number of individuals. Thank you to Brandy Dionne and Pilar Ciravolo from the Yale Human Research Protection Program for their endless patience. Thank you to Desmond Walker for his assistance with obtaining data from Yale’s EMR. Thank you to American Medical Response-­‐New Haven, Yale-­‐New Haven Hospital, the Connecticut Medical Examiner, and the New Haven Police Department for graciously sharing their records, without which we could not have undertaken this research. Thank you to Christal Esposito, Douglas Barber, Vanessa Kuhlor, and Michelle Wu for help collecting data and establishing the trajectory of the project. Thank you to David Cone and Liudvikas Jagminas for helping to access hospital and pre-­‐hospital data. Thank you to Alexei Nelayev for advice and assistance regarding the Institutional Review Board. Thank you to Richard Spano for helping to shape the project, for contributing data and knowledge regarding the police department, and for many discussions along the way that guided the development of the research. Finally, thank you to Lori Post for her wise and careful oversight of the project.