Editorial: Gun Violence--Risk, Consequences, and Prevention.

Abstract

Firearm injury is one of the leading causes of death in the United States (1). Firearm-related homicide was the leading cause of death for blackmen aged15–34years in 2012,whereas firearm-related suicide was the second leading cause of death for white males aged 10–34 years (1). In 2013, there were 32,888 individuals in the United States who died from a firearm-related injury, including 21,175 suicides, which is the equivalent of 1death byfirearmevery 16minutes (2).Most firearm-related violent deaths are the result of suicide; 60.5% of deaths from firearm-related violence were due to suicide in 2002–2012 (3). Firearm injuries accounted for $229 billion spent on costs associated with health care, criminal justice, loss of income, pain, suffering, and lost quality of life in 2013 (4). The current volume of Epidemiologic Reviews provides a comprehensive summary of the evidence on the epidemiology of firearm violence, including sources of firearm violence and approaches to preventing it. The papers in this volume span 3 themes, with many articles addressing more than 1. The first and central issue addressed in this volume is the link between access to firearms and violence. In individuallevel and ecologic studies, investigators have consistently found a relationship between firearm availability and firearmrelated injury; however, these results have often been questioned because of lack of control for confounding and an inability to establish the directionality of the relationship. Zeoli et al. (5) conducted a narrative review on access to firearms and the risk of intimate partner violence. Tracy et al. (6) reviewed the evidence on the associations of exposure to gun violence in one’s social network with carrying a firearm and violent behaviors. Santaella-Tenorio et al. (7) examined the literature on the impact that laws aimed at restricting firearm access had on the number of firearm homicides, suicides, and deaths from unintentional injury. The most notable paper in which this issue was addressed was by Miller et al. (8), who assessed whether the consistent relationship between household firearm availability and suicide might be explained by unmeasured confounding. They found that for an unmeasured confounder to completely explain the observed associations, it would have to be as strongly associated with suicide as was the strongest psychiatric risk factors and be more imbalanced across homes with and without firearms than are any known suicide risk factors. Their paper highlights the importance of quantifying bias and testing whether it is likely to explain the associations observed in the literature. Such an empirical assessment raises the discourse about the contribution of firearm availability to morbidity and mortality and provides a strong foundation for policy (8). Second, this issue of Epidemiologic Reviews includes papers in which investigators considered firearm violence as part of a correlated set of risky behaviors, including substance use and belonging to deviant social networks. In 3 papers (9– 11), authors reviewed the evidence on the relationship between substance use and firearm violence. Although it has been widely assumed that there is a causal relationship between substance abuse and firearm-related activities, the evidence on this association is still inconclusive. McGinty et al. (9) examined the relationship between use of controlled substances and violence, and Branas et al. (10) conducted a review and meta-analysis of the research on the relationship between alcohol use and firearms. Chen and Wu (11) took a broader approach and presented a narrative review on the relationships between use of different types of substances (i.e., alcohol, tobacco, marijuana, cocaine/crack) and firearmrelated activities (i.e., firearm access, firearm carrying, unsafe firearm handling, and firearm violence). The reviews revealed a positive association between substance use and firearmrelated activities, although the associations often disappeared or decreased after adjustment for psychiatric disorders, especially antisocial personality disorder. The relationship between the use of controlled substances and firearm-related suicide was the most robust to confounding. Following on the notion of correlated risk behaviors, Tracy et al. examined the evidence on the transmission of firearm violence through social networks (6). They found support for the idea that the risk of weapon-related violence increases through close connection with someonewho has perpetrated or been a victim of weaponrelated violence. However, there were only 3 studies in which formal network analysis techniques were applied to examine the structure of social networks and their influence on firearm violence, and they all focused on co-offending networks. The third key theme was related to approaches to the prevention of firearm violence, ranging from individual-level