No Evidence of Suicide Increase Following Terrorist Attacks in the United States: An Interrupted Time‐Series Analysis of September 11 and Oklahoma City

Abstract

There is substantial evidence of detrimental psychological sequelae following disasters, including terrorist attacks. The effect of these events on extreme responses such as suicide, however, is unclear. We tested competing hypotheses about such effects by employing autoregressive integrated moving average techniques to model the impact of September 11 and the Oklahoma City bombing on monthly suicide counts at the local, state, and national level. Unlike prior studies that provided conflicting evidence, rigorous time series techniques revealed no support for an increase or decrease in suicides following these events. We conclude that while terrorist attacks produce subsequent psychological morbidity and may affect self and collective efficacy well beyond their immediate impact, these effects are not strong enough to influence levels of suicide mortality.

Effect of 11 September 2001 terrorist attacks in the USA on suicide in areas surrounding the crash sites

“…This study's positive findings stand in contrast to negative findings from two other very recently published studies of post-9/11 New York City suicide rates. 27,28 As in this study, a drop in suicides after 9/11 was noted in both reports, but the finding was not regarded as significant in either. There are important methodological differences across studies.…”

Suicidality Risk and (Repeat) Disaster Exposure: Findings From a Nationally Representative Population Survey

“…Other studies identified a delayed increase in suicidality further down the track (Chou et al, 2007;Kessler et al, 2008). Despite the lack of systematic reviews of suicide research in man-made disaster contexts, the relatively few existing studies, which mainly investigated suicide trends in relation to the September 11, 2001, terrorist attacks in the United States, indicated no significant changes in overall suicide mortality rates (Mezuk et al, 2009;Pridemore, Trahan, & Chamlin, 2009) and only shortlived initial increases (De Lange & Neeleman, 2004) or decreases (Salib, 2003) in post-9/11 suicide rates overseas. Studies investigating nonfatal suicidal behavior following 9/11 have shown increases in suicide attempts requiring medical admission (Starkman, 2006) and longer-term suicidal ideation in primary care (Neria et al, 2013), while also identifying an immediate but short-lived decrease in suicide attempts abroad (Detsky, Sivilotti, Kopp, Austin, & Juurlink, 2005).…”

Research Designs for Intervention Research with Small Samples II: Stepped Wedge and Interrupted Time-Series Designs

“…Stallings-Smith, Zeka, Goodman, Kabir, & Clancy (2013) used the ITSD to examine the effectiveness of a smoking ban in reducing rate of heart disease and mortality. The ITSD can also be applied in evaluating the effects of a critical or catastrophic event on health outcomes; Pridemore, Rahan, and Chamlin (2009) evaluated the impact of the September 11 World Trade Center attacks and the Oklahoma City bombing on the rate of suicide. The ITSD is especially useful when there is a clearly identified time point of intervention or policy change, and less useful with outcomes that are more time continuous, and without such clear, critical time points.…”