Railway suicides are less likely to occur on rainy days: Evidence from Japan

Background: Patrols at stations and along railway lines can reduce the number of railway suicides; however, it is not sufficiently clear when railway suicides are most likely to occur. Aim: We examined the relationship between daily rainfall and the occurrence of railway suicides. Methods: We received the locations and daily data on the occurrence of railway suicides from a major railroad company in Japan. We also collected rainfall data from the Japan Meteorological Agency database for a roughly central locations of the railroad company. The study covered a period of five years, from April 2016 to March 2021. Results: Suicides occurred on 23 rainy days (3.9%) and 92 non-rainy days (7.4%). The incidence of suicides on rainy days was significantly lower than that on non-rainy days. Limitations: We were not able to obtain daily data on the number of rail passengers; therefore, could not rule out the possibility that the suicide incidence rate is lower on rainy days because the number of railroad users is lower on such days. Conclusion: Information about the weather could be used to improve the efficiency of patrols to prevent railway suicides.