Unintended Consequences of Installing Platform Screen Doors: Displacement and Substitution for Suicide Attempts

This research investigates the displacement and substitution effects of installing physical barriers in metro stations for suicide prevention. Although physical barriers are considered effective at reducing suicides at a given metro station, it remains unexplored whether their installation actually decreases suicide attempts at the macro level. Exploiting the timing of the installation and using platform-level novel data on suicide attempts, we find new evidence showing that installing physical barriers at metro stations causes (1) displacement to other lines without barriers in the same station, (2) displacement to other single-line stations, and (3) substitution to other suicide methods.