b'Figure 12 illustrates the interdependence between the links in the chain of survival, by highlighting how rapid 911 response and bystander CPR (bCPR) work in tandem to improve patient survival. Bystander CPR helps provide critical and timely intervention while 911 vehicles are en route to the scene. By comparing the same patient subgroups in Figure 11 and Figure 12, one can observe how survival is elevated when bystander CPR is performed. EARLY CPROne of the critical interventions for successful resuscitation is early CPR. Starting CPR before the arrival of an ambulance significantly increases a patients chances of survival. In 2024, bystander CPR was initiated on 41.7% of CARES patients. Of note, CARES excludes events witnessed by 911 Responders as well as those that occurred in a nursing home or healthcare facility from our bystander CPR rate, as CPR in these scenarios is typically performed by trained medical providers.Bystander CPR provision was strongly correlated with arrest witness status (Figure 13). Bystander CPR was initiated after 50.1% of bystander witnessed events, compared to 35.2% of unwitnessed events (p.0001).39Figure 13. Bystander CPR provision by arrest witness status.'