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Cited by 17Suicide and Self-Harm StudiesHomicide, Infanticide, and Child AbuseInjury Epidemiology and Prevention

Predictive Factors Associated With Methods of Suicide: The Korean National Investigations of Suicide Victims (The KNIGHTS Study)

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Kim, Hyewon, Kim, Yuwon, Lee, Gusang, Choi, Jin Hwa, Yook, Vidal, Shin, Myung-Hee, Jeon, Hong Jin·2021·Frontiers in Psychiatry
DOI 10.3389/fpsyt.2021.651327PMC PMC8149594
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Abstract

Background: Because the suicide mortality depends on the lethality of suicide methods, the identification and prediction of suicide methods are important for suicide prevention. Methods: Examination data of suicide decedents were collected based on police reports. Suicide decedents were divided into groups according to the suicide methods (hanging, gas poisoning, pesticide poisoning, jumping, drug poisoning, and drowning) they used. Predictive factors for each suicide method in comparison to other suicide methods were identified. Results: Among 23,647 subjects, hanging was the most common method of suicide. Regarding gas poisoning, the history of previous suicide attempt was a risk factor and being age of 65 or older was a protective factor. Being age of 65 or older showed a highly strong association with suicide by pesticide poisoning. Being age of 18 or younger and the presence of schizophrenia were associated with jumping. A history of psychiatric outpatient treatment was a risk factor for drug poisoning. Regarding suicide by drowning, schizophrenia was a risk factor, while being age of 65 or older was a protective factor. Limitations: Only eight out of a total of 17 regions in South Korea were examined and included in the data of this study. Also, the methods of suicide were defined as one method that directly caused the death, which could undermine other less fatal methods used. Conclusions: There were differences in predictive factors according to the method of suicide. Predicting the method of suicide in people at high risk for suicide stands to be an important strategy for suicide prevention in clinical settings.

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  • Depression and bad social conditions are related to a greater risk of suicide attempts.

    “Depression and bad social conditions are related to a greater risk of suicide attempts, and family and social support is crucial to protection from suicide attempts.”

    From Toxicological Findings of Self-Poisoning Suicidal Deaths: A Systematic Review by Countries (2022) · cites this paper as [58]

    The Discussion (page unavailable) states that depression is an independent risk factor for suicide. But the paper studies people who died by suicide and differences among suicide methods; it does not establish that depression or adverse social conditions increase the risk of suicide attempts. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • Depression was the most relevant risk factor associated with suicide.

    “Depression was the most relevant risk factor associated with suicide.”

    From Toxicological Findings of Self-Poisoning Suicidal Deaths: A Systematic Review by Countries (2022) · cites this paper as [58]

    The Discussion (page not available in our copy) calls depression an independent risk factor for suicide, supporting its association with suicide. It does not rank depression as the most relevant risk factor; the Results compare risk factors for different suicide methods rather than ranking overall suicide risk. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

  • There is a robust association between suicide and depression.

    “The robust association between suicide and depression demands that greater attention be paid to diagnosing this mental disorder, particularly in primary healthcare, and the interventions designed to treat depression are considered as essential to preventing suicide [12,58].”

    From Toxicological Findings of Self-Poisoning Suicidal Deaths: A Systematic Review by Countries (2022) · cites this paper as [58]

  • Isolation may trigger events related to vulnerability and lead to suicide.

    “Isolation may trigger events related to vulnerability and lead to suicide.”

    From Toxicological Findings of Self-Poisoning Suicidal Deaths: A Systematic Review by Countries (2022) · cites this paper as [58]

    The Results section reports factors associated with particular methods of suicide, and the Discussion addresses method-specific prevention. Neither the supplied passages nor searches for isolation, social isolation, and vulnerability describe isolation triggering vulnerability-related events that lead to suicide. No page numbers are available in our copy. (LLM, conf=0.76)

    Experimental — accuracy not yet measured

  • Both unemployment and low educational levels are significant risk factors for suicide attempts.

    “Both unemployment and low educational levels are significant risk factors for suicide attempts as they are associated with social drawbacks that may predispose an individual to suicidal behavior [49,56,57,58].”

    From Toxicological Findings of Self-Poisoning Suicidal Deaths: A Systematic Review by Countries (2022) · cites this paper as [58]

    The Results section reports employment status in analyses of suicide methods, using unemployed people as the reference group; it does not establish unemployment as a risk factor for suicide attempts. A search for educational level found no passage addressing low education as a risk factor for attempts. The Discussion distinguishes suicide attempts from completed suicide but does not make the attributed claim (page numbers unavailable). (LLM, conf=0.76)

    Experimental — accuracy not yet measured

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Authors
Kim, H., Kim, Y., Lee, G., Choi, J. H., Yook, V., Shin, M.-H., & Jeon, H. J.
Affiliations
  • Hanyang University Seoul Hospital (KR)
  • Samsung Medical Center (KR)
  • Sungkyunkwan University (KR)
Corresponding author
Jeon, Hong Jin
ORCID
Venue
Frontiers in Psychiatry
Publisher
Frontiers Media SA
Published
2021-05-12
Volume
12
Pages
651327-651327
ISSN
1664-0640 (ISSN-L)
DOI
10.3389/fpsyt.2021.651327
PMC
PMC8149594
OpenAlex
W3162267348
Cited by
17
References
35
Citations by year
2026: 1 · 2025: 8 · 2024: 1 · 2023: 3 · 2022: 2 · 2021: 2
FWCI
1.36
Type
journal article
Language
en
Open access
Licence
Locations
  • Frontiers in Psychiatry (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
Sungkyunkwan University
Topics
  • Social Sciences › Psychology › Clinical Psychology › Suicide and Self-Harm Studies
  • Social Sciences › Sociology and Political Science › Homicide, Infanticide, and Child Abuse
  • Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Injury Epidemiology and Prevention
Keywords
suicide methods, predictive factors, hanging, gas poisoning, pesticide poisoning, jumping, drug poisoning, drowning, previous suicide attempts, schizophrenia, age as protective factor, suicide prevention, suicide decedents

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