An Evaluation of Means Restriction on Preventing Jumping Suicides: A Case Study at Cornell University

Abstract

Background: Jumping from a height is an uncommon yet highly lethal means of suicide. While multiple factors contribute to a person’s desire to die, it is possible to reduce the risk of suicide by restricting access to the means of lethal jumps. Cornell University’s main campus, located in Ithaca, New York, is known for its natural beauty, spectacular gorges, and dramatic waterfalls. There are multiple pedestrian and vehicle bridges on or near Cornell’s campus that cross Fall Creek Gorge and Cascadilla Gorge. These bridges and adjacent cliffs have developed an iconic status for suicide due to multiple jumping suicides among enrolled Cornell students and other individuals. Cornell University and the City of Ithaca have a unique challenge where multiple bridges and gorges collectively had become a “hotspot” for suicide. Additionally, Cornell University developed a reputation as a “suicide school” due to its history with jumping suicides (Epstein, 2010).

Following a cluster of Cornell student suicides during the 2009 – 2010 academic year, Cornell University implemented new permanent suicide means restriction efforts by installing suicide safety barriers, including steel wire mesh nets or vertical barriers on the bridges, and fences along the adjacent gorges, as a universal, population-level, environmental strategy to prevent further jumping suicides. Cornell University has not yet evaluated the impact of the installation of means restriction on suicide jumps.

Objectives: There are four aims of this dissertation: 1) to determine the impact of means restriction installed on the eight bridges on or near Cornell University’s campus (the East Hill bridges) from 2010 – 2022 on lethal and non-lethal suicide jumps; 2) to determine if Cornell student suicide deaths by jumping were displaced to any other jumping locations or tall structures after the installation of suicide bridge barriers at Cornell University beginning in 2010; 3) to examine the effect of the suicide bridge barriers on the overall suicide rate by non-jumping methods among enrolled Cornell University students; and 4) to understand the rates of suicidal ideation, suicide attempt behavior, and suicide deaths by any method among Cornell University enrolled students over time.

Design: Natural experiment; interrupted time series.

Setting: Cornell University located in Ithaca, New York, USA

Aims and Methods: Retrospective secondary data analysis was conducted to examine the four research aims of this study. Aim 1 was to determine the impact of means restriction on lethal and non-lethal suicide jumps from the East Hill bridges, Aim 2 was to determine if suicide jumps were displaced to a different jumping location among Cornell enrolled students, Aim 3 was to determine the impact of the means restriction intervention on suicide deaths by non-jumping methods and if method substitution occurred, and Aim 4 was to understand the trend in overall rates of self-reported suicidal ideation, suicide attempt behavior, and overall suicide rates among Cornell University enrolled students over time. Using an interrupted time series design, Poisson regression was used to assess changes in Cornell student annual suicide counts and rates by jumping from the East Hill bridges or adjacent cliffs and the annual suicide counts and rates by any method before (January 1, 1990 – March 31, 2010) and after (April 1, 2010 – December 31, 2022) installation of the suicide bridge barriers. Counts and rates of suicide deaths were also examined before and after the intervention. Suicide jumps and death data was obtained from Cornell University officials. Secondary data analysis was conducted to identify trends in suicidal ideation and suicide attempt behavior over time among Cornell University undergraduate college students using self-reported aggregate survey data conducted by Cornell University. Secondary data analysis was also conducted to identify trends in overall suicide rates among Cornell University enrolled college students over time.

Results: For Aim 1, there was a decrease in both the number and rate of lethal suicide jumps and the number of non-lethal suicide jumps among Cornell enrolled students following the installation of additional means restriction on the East Hill bridges on or near Cornell’s campus. Additionally, there was a decrease in the number of lethal and non-lethal suicide jumps among other individuals who were not enrolled students following means restriction on the East Hill bridges or nearby gorge cliffs. There was a total of 30 lethal and non-lethal jumps (27 lethal, 3 non-lethal) that occurred from the East Hill bridges or nearby gorge cliffs in a 21-year study period before means restriction was implemented and only 5 lethal and non-lethal jumps (3 lethal, 2 non-lethal) from the same location in a 12-year study period after means restriction was installed. For Aim 2, there were no instances of displacement of suicide jumps from the East Hill bridges to some other location on Cornell’s campus following the installation of means restriction and there were two possible instances of displacement of suicide jumps from the East Hill bridges to some other location off-campus. For Aim 3, there may have been some evidence of method substitution, particularly among Cornell enrolled graduate and professional students. For Aim 4, self-reported suicidal ideation among Cornell undergraduate students increased over time from 7.5 percent in 2005 to 14.0 percent in 2021, self-reported suicide attempt behavior increased slightly overtime from 1.1 percent in 2005 to 1.6 percent in 2021. Additionally, the average overall suicide rate among Cornell enrolled students for the 21-year study period before the means restriction intervention was 7.4 deaths per 100,000 and it decreased to 6.8 deaths per 100,000 for the 12-year study period after the intervention.

Conclusion: The installation of means restriction on the East Hill bridges and adjacent gorges was protective and contributed to a reduction in jumping deaths and was associated with a decrease in overall suicides while the national suicide rate was increasing. The relatively infrequent behavior of suicide, and jumping suicides specifically, makes it difficult to study. However, this research adds to the evidence base related to means restriction as an evidence-based environmental, population-level strategy to prevent jumping suicides, especially at known hot spots.