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Prevalence and Risk Factors of Depression and Posttraumatic Stress Disorder After a Mass Shooting

NCJ Number
JAMA Network Open Volume: 7 Issue: 3 Dated: 2024 Pages: e242739
Date Published
March 2024
5 pages

This article describes a research study, its methodology and outcomes, which found that witnesses and survivors of the 2017 mass shooting at a music festival in Las Vegas continued to have substantial mental health challenges even four years later, emphasizing the need for sustained mental health support; the authors recommend implementing long-term support strategies.


On October 1, 2017, a lone gunman shot and killed 60 people and injured 867 others at the Route 91 Harvest Music Festival in Las Vegas, Nevada, making this mass shooting the deadliest in US history. Witnesses and survivors of mass violence incidents (MVIs) often experience depression and posttraumatic stress disorder (PTSD). However, the psychological sequelae and associated factors among witnesses and survivors of the Las Vegas MVI have yet to be examined. In this study, the authors documented the prevalence and risk factors of major depressive episode (MDE) and PTSD among witnesses and survivors of the Las Vegas MVI using 2021 data, four years after the incident. Participants were adult witnesses and survivors of the shooting who were recruited from a list of those who were eligible for but had not necessarily received services from the Vegas Strong Resiliency Center. Witnesses were defined as those who were present at the scene and/or sustained physical injuries, whereas survivors included family members or friends of people who were physically injured or killed. Data were collected between September 3 and November 11, 2021, using a self-administered online survey. The Boston University and Medical University of South Carolina Institutional Review Boards approved this cross-sectional study. Participants provided written informed consent. The authors followed the STROBE reporting guideline. The authors report on their measurement of MDE using a modified version of the National Women’s Study Depression module and PTSD using the National Stressful Events Survey PTSD module and discuss their methodology for data collection and analysis. Results indicated that adequate social support was associated with reduced risk of both past-year MDE and PTSD, and that physical injury and low social support were associated with higher risk for MDE and PTSD. Table 2 provides results of the regression analyses. (Published Abstract Provided)

Date Published: March 1, 2024