Accident or suicide among road traffic fatalities
Article in Review: Andersson, A.L. & Sokolowski, M. (2022). Accident or suicide? Improvement in the classification of suicides among road traffic fatalities in Sweden by extended psychosocial investigations during the years 2010 – 2019. Journal of Safety Research, https://doi.org/10.1016/jsr.2021.11.004
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Summary
This Swedish study aimed to investigate if more of the deaths attributed to road accidents were, in fact, suicides. The study describes the criteria that have historically been used to clarify suicides in road accidents, along with the impact of extending investigation around suicides that could potentially have been attributed to road accidents. The study found that by carrying out more investigation in these situations, there was a decrease in the number of road traffic fatalities being classified as accidents or being listed as undetermined and an increase in suicides.
Road accidents and suicide
According to the World Health Organisation (2014, 2019) suicide is the second leading cause of death among ages 15-29, being exceeded only by road injuries. There is believed to be an underestimation of road traffic deaths that occurred through suicide, mainly due to an absence of necessary information. In 1997, the Swedish government began recording extended data about toad traffic fatalities, by recording data related to the person, the vehicle, the road and the accident event. This review of this data suggested that about 5% of road traffic deaths between 1997 and 2002 could be attributed to suicide.
In 2008, the Swedish government commenced a more focused attempt to record road fatalities as either accidents or suicide. Determining one or the other of these outcomes is a complex task. This increased effort results in road traffic fatalities being identified as either
• Accident
• Suicide
• Natural death (Where a person died of causes unrelated to the accident, within 30 days of the accident)
• Undetermined
Methods
Four different data sets and classifications were considered to enable a more accurate assessment of road traffic deaths that occurred.
- Three alternative criteria for suicide in road traffic deaths were considered, where there was a farewell message or clear intention of suicide, cases where depression, mental illness, stressful life event or other factors had been noted, or where there was a strong indication of suicide.
- A five-grade classification scale.
- Information such as autopsy reports, photos, information from the police, press clippings and notes from the technical investigation of the car.
- Psychosocial data including case notes, and demographic information including marital status, education, work situation, recent trauma, health, mental illness and use of drugs and alcohol among others, plus information related to antisocial behaviours, increased aggression and previous suicide notes or recorded intention.
Data for the 2012 intra-year was considered with these extended investigation criteria, and compared to data from the period 2010-2012 as a control, and then during 2013-2019 through the continued use of the extended criteria.
Findings and recommendations
• There were an additional 14 road deaths determined to be suicide in the 2012 year- an increase of 63%
• Of these additional 14 deaths determined to be suicide, 12 had previously been classified as “undetermined”
• Using the enhanced investigation approach, an average of 9 additional suicides were identified for each of the years 2013-2019
• Both the 2012 intra-year and the 2013-2019 vs. 2010-2012 comparisons showed that the use of the extended investigations resulted in at least a 60% increase in the number of suicides among road traffic fatalities.
The use of more extensive and wide-ranging investigations into road traffic fatalities is important to enabling a more cohesive picture of the number of suicides on the roads.