Evolution of Firearm Violence over 20 Years: Integrating Law Enforcement and Clinical Data

Data linking ballistics to injury are lacking. To address this data chasm, a partnership with law enforcement was developed to describe clinical outcomes from specific firearms.

A random sample of patients with gunshot wounds over a 20-year period ending in 2015, was identified. Circumstances of incident, firearm type, and/or caliber were extracted from police reports. Data on demographics, mortality, injury severity, and clinical outcomes were collected from the trauma registry, and these datasets were linked. Firearms were stratified by velocity (high > 2,500 ft/sec; low < 1,200 ft/sec) and caliber (large = .40 and .45; small = .20 and .25) and compared over time.

Police reports were obtained on 366 patients who had a gun type or caliber documented. The majority were male (82%) with a median age of 28 years. Twenty-one percent of patients had an Injury Severity Score > 25, 60% required immediate operative intervention, and overall mortality was 13%. The use of large caliber firearms increased from 4% (1996 to 2000) to 33% (2011 to 2015); small caliber guns decreased from 33% to 7% over the same time period (p < 0.0001). High velocity firearm usage significantly increased (p = 0.0320). Recovered shell casings doubled from the first decade to the second (2 vs 4; p = 0.0006). Both median New Injury Severity Score (p = 0.0488) and hospital days (p = 0.0321) increased from 1996 to 2015.

Larger caliber and higher velocity firearms have significantly increased over the past 20 years in conjunction with injury severity, hospital days, and mean number of gun-related homicides per year (112 in 1996 to 2000 vs 143 in 2011 to 2015). Robust data sharing partnerships can be built between police and trauma centers to address the dearth of data on firearm crime and resulting injury.