Crowding and Violent Behaviour: The Influence of Patient Density on Violent and Self-Harming Behaviour at a Medium Secure Unit

This study examines the influence of patient density (crowding) and number of potential perpetrators on the number of incidents of violence and self-harm at a medium secure unit. Of 2,053 incidents examined over a period of 974 days, 73% were perpetrated by 20% of the patients, the majority by patients identified as potential perpetrators. Increased patient density was not associated with increased risk of violence or self-harm. There was no evidence to suggest that the presence of those identified as potentially violent or self-harming increased the risk of others engaging in such behaviour.