J Korean Med Sci.  2025 May;40(19):e59. 10.3346/jkms.2025.40.e59.

Practicability of Suicide Reduction Target in Korean Suicide Prevention Policy: Insights From Time Series Analysis

• Ryu S
• Baek SH
• Jhon M
• Kim H
• Lee JY
• Kim JM
• Kim SW

• KMID: 2568103
• DOI: http://doi.org/10.3346/jkms.2025.40.e59

Abstract

Background
This study evaluated the practicability of the suicide rate reduction target set by the current national suicide prevention policy in Korea, the fifth Master Plan for Suicide Prevention (2023–2027). This policy aims to lower the suicide rate from 26/100,000 in 2021 to 18.2/100,000 by 2027.
Methods
We utilized monthly suicide statistics data from 2011 onwards. Using Bayesian regression and Autoregressive Integrated Moving Average (ARIMA) models, we conducted interrupted time series analyses to estimate the effect of the previous policy, the National Action Plan for Suicide Prevention (2018–2022), on suicide rates. We assumed this as the additional suicide reduction expected from the current policy. We generated point predictions and simulations for suicide rates from 2023 to 2027 using Bayesian regression and ARIMA models.
Results
The interrupted time series analyses did not reveal a significant reduction in suicides attributable to the previous policy. Point predictions from the two models indicated that the suicide rate would remain approximately 24/100,000 in 2027. Almost all of the simulations of the 2027 suicide rate did not meet the policy target of 18.2/100,000.
Conclusion
The findings suggest that the Korean government’s suicide rate reduction target for 2027 is likely unattainable based on current trends and the limited effectiveness of previous policies. The objectives of suicide prevention policies should be evidence-based, attainable, and accountable.

Keyword

Suicide; Policy; Interrupted Time Series Analysis; Prediction; Simulation

Figure

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  Fig. 1 Time series of actual and predicted counterfactual monthly suicide numbers before and after the implementation of the National Action Plan for Suicide Prevention. The dashed blue lines represent the predicted suicide numbers, and the surrounding blue area represents the 95% credible interval (A) or 95% confidence interval (B). The solid black line indicates the actual suicide numbers. The black bars represent the difference between the actual and counterfactual suicide numbers, while the gray bars represent the raw residuals.ARIMA = Autoregressive Integrated Moving Average.

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  Fig. 2 Annual suicide rates predicted by Bayesian regression model: fifth Master Plan for Suicide Prevention (2023–2027). The solid black line indicates the official suicide rates up until 2022, while the solid gray line represents the provisional suicide rate for 2023. The dashed blue lines and the gray area represent the point prediction and simulations of suicide rates from 2023 to 2027, respectively. The dotted red line illustrates the suicide reduction target set by the fifth Master Plan for Suicide Prevention.

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  Fig. 3 Annual suicide rates predicted by ARIMA model: fifth Master Plan for Suicide Prevention (2023–2027). The solid black line indicates the official suicide rates up until 2022, while the solid gray line represents the provisional suicide rate for 2023. The dashed blue lines and the gray area represent the point prediction and simulations of suicide rates from 2023 to 2027, respectively. The dotted red line illustrates the suicide reduction target set by the fifth Master Plan for Suicide Prevention.ARIMA = Autoregressive Integrated Moving Average.

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