“…The cardiac arrest database followed the Utstein Style, an objective tool to access cardiac arrest patients published by American Heart Association (AHA) and European Resuscitation Council 25,26) , and emergency medicine residents wrote the database based on patient history and 119 emergency activity records. Among other records made before hospital arrival, this study collected the location of cardiac arrest, whether cardiac arrest was witnessed, the time cardiac arrest was noticed or witnessed by bystanders, the time when it was reported to the emergency medical service system, the time when 119 first responders arrived at the scene, whether a bystander performed chest compressions or used the automated external defibrillator (AED) before 119 first responders arrived, the AED application by 119 first responders and the initial electrocardiogram (ECG) rhythm, and whether the patient had a return of spontaneous circulation (ROSC) before arriving at the Emergency Department.…”