The HEROES study examines the impact of the Region of Lifesavers community first responder system on survival rates following out-of-hospital cardiac arrest. It monitors all cases of out-of-hospital cardiac arrest attended by emergency medical services across 11 regions during two eight-month observation periods — one before and one after the system’s implementation.

The study was initiated by the Region of Lifesavers organisation and receives support with data management from the Centre for Emergency and Rescue Medicine at the University Medical Centre Freiburg.

Study period: 1 January 2024 – 31 August 2025