Citation

Callcut RA, Robles AM, Kornblith LZ, Plevin RE, Mell MW. J. Trauma Acute Care Surg. 2019; ePub(ePub): ePub.

Affiliation

University of California, Davis, Department of Surgery, Sacramento, CA, USA.

Copyright

(Copyright © 2019, Lippincott Williams and Wilkins)

DOI

10.1097/TA.0000000000002399

PMID

31162332

Abstract

INTRODUCTION: Granular data on gun sales has been historically difficult to obtain. In 2016, California (CA) made monthly data from 1996-2015 publically available. Control charts are a method to analyze how a process changes over time in response to non-routine events. We utilized this technique to study the impact of US mass shootings on CA gun sales.

METHODS: Monthly gun sales were provided by the CA Department of Justice and monthly fatalities from the CDC Wonder Death Certificate Registry. Mass shooting events were obtained from after-action reports, news media, and court proceedings. Time ordered data were analyzed with control charts with 95% CIs (UCL, LCL) using QiMacros.

RESULTS: 9,917,811 individual gun sales occurred in CA with a median monthly rate of 41,324 (range 20,057 - 132,903). A median 263 people lost their lives monthly from firearms (124 homicide, 128 suicide), totaling 53,975 fatalities from 1999-2015. 15/21 current deadliest mass shootings occurred during this study period with 40% from 2012-2015. Also, 36 school shootings occurred during the study (mean 5 deaths, range 0-33; 6 injuries, range 0-23) with 31% in 2012-2015 at rate of 3 events/year vs. 1.4 events/year in the 17 prior years (p<0.05). Sales were generally consistent from 1996-2011 (except post Columbine, Col). Starting in 2011, sales exceeded the 95% predicted UCL every single month. Before October 2011, there was no statistically significant sustained effect of mass shootings on sales (except Col); however, since a statistically significant proportional spike in sales occurred in the months immediately following every single deadliest mass-shooting event. Every year since 2012, CA has strengthened gun laws in response to mass shootings yet sales have risen immediately preceding enactment of these laws each January.

CONCLUSION: Gun sales are more frequent since 2012, with an additional increase following both mass shootings and legislative changes enacted in response to these shootings. LEVEL OF EVIDENCE: Epidemiology, Level III.

Language: en