Evaluating the effectiveness of barrier installation for preventing railway suicides in Hong Kong

Railway suicide is a serious mortality issue. Most attempters are unmarried psychotic young men under psychiatric care having a high level of lethal intent. Installation of platform screen doors (PSDs) to limit access to the track has been suggested as an effective way for prevention. This study aims to examine the effectiveness of installing PSDs for preventing railway suicides; any sign of substitution of suicide location; and changes in psychiatric profile of suicide deceased after the PSD installation in the subway system of Hong Kong.

Cases of railway suicide and related information from 1997 to 2007 were provided by the railway operators and the Coroner's Court. The effectiveness of installing PSDs was assessed through a quasi-experimental setting. Poisson regression and chi-squared test were used.

Over the 11-year study period, a total of 76 railway suicide cases (0.71% of all suicides) were reported. A significant reduction of 59.9% (p=0.0003) in railway suicides was found after the PSD installation. Analyses confirmed that there was no significant sign of substitution by displacing potential attempters to unsealed platforms (p=0.9051). Those having psychosis would be better protected as no suicide cases with such psychiatric background were reported after the installation of PSDs.

It has not considered the potential economic benefits of PSD. It is difficult if not possible to examine whether the potential attempters would substitute to an alternative method of suicide.

This study shows that PSDs can effectively prevent suicides with no substitution by "delethalizing" the image and altering people's perception about the desirability of railway suicide. Railway operators should extend the coverage of PSD to all railway stations in Hong Kong without any delay.