Background

Persons tend to estimate the likelihood of events, such as the risk for homicide versus suicide, in proportion to the ease with which they can retrieve examples of these incidents from memory (1). Because the recency of personal experience and media coverage can influence this retrieval (1–3), misperceptions about the relative frequency of suicide versus homicide—the leading causes of intentionally inflicted (that is, violent) death from external causes (such as firearms)—may be common. In the United States, suicide is twice as common as homicide, and suicide by firearm is more common than homicide by firearm (4). However, no nationally representative study has assessed public perceptions of the relative frequency of these leading causes of violent death. This study addresses this subject. We hope that identifying the scope of actuarial misperceptions among the U.S. population in general and among those who own or live with firearm owners in particular might facilitate discussions about firearm ownership and storage.

Objective

To describe public misperceptions about the relative frequency of violent death by intent (homicide vs. suicide) and means (firearm vs. nonfirearm) at the national level.

Methods and Findings

We used data from the National Firearms Survey, a nationally representative Web-based survey of U.S. adults conducted by Growth for Knowledge in April 2015. Details are described elsewhere (5). A total of 3949 participants were presented with 4 options on the intent and means of violent death (homicide with a gun, homicide with a weapon other than a gun, suicide with a gun, and suicide by a method other than a gun) and asked to rank order the frequency of these outcomes in their state in an average year (Supplement).

We used the Centers for Disease Control and Prevention’s Web-based Injury Statistics Query and Reporting System to rank these 4 options in each state between 2014 and 2015 (the year before the survey was conducted and the year that it was conducted, respectively) (4). Survey respondents were characterized by their ability to correctly rank the frequency of violent death in their state by intent and means.

Between 2014 and 2015, more suicides than homicides occurred in every state. Suicide by firearm was the most frequent cause of violent death in 29 states (Figure). A total of 3811 respondents answered the question on the relative frequency of the intent and means of violent death in their state. Only 13.5% (95% CI, 11.5% to 15.8%) of U.S. adults correctly identified the most frequent cause of violent death (Table). Furthermore, 20.0% (CI, 10.3% to 35.4%) of health care professionals among the 1880 respondents who reported their occupation and 12.4% (CI, 8.3% to 18.2%) of U.S. adults with a history of mental illness answered correctly. For violent deaths involving firearms, 25.9% (CI, 23.2% to 28.8%) correctly identified the most frequent intent. Correct identification did not vary by respondents’ firearm ownership status.

Discussion

Suicide was more common than homicide in all states, and suicide by firearm was more common than homicide by firearm in all states except Illinois, Maryland, and New Jersey. However, most U.S. adults—including health care professionals—did not identify the most frequent intent and means of violent death in their state. These findings are consistent with the well-established relationship between risk perception and the ease with which a pertinent categorical example can be summoned from memory, which in most persons is probably affected by the salience of homicides in media coverage (1, 2).

Our findings suggest that correcting misperceptions about the relative frequency of firearm-related violent deaths may make persons more cognizant of the actuarial risks to themselves and their family, thus creating new opportunities for prevention. If communication strategies could enhance the accuracy of perceived risk, some persons living in households with firearms might be motivated to remove these weapons from their home or at least keep unsafely stored firearms locked and unloaded to reduce access by potentially vulnerable family members. Future research should evaluate whether and under what circumstances promoting awareness about the relative frequency of suicide versus homicide (overall and by firearm), combined with evidence that firearm access increases the risk for suicide several-fold, enhances more accurate risk perception and motivates behavioral change regarding firearm storage.