Various studies have shown that rapid and correctly performed cardiopulmonary resuscitation (CPR) significantly increases the survival rate after cardiac arrest. Such a situation can affect anyone, anywhere and at any time, making it all the more important to master the basic skills and abilities of Basic Life Support (BLS). Thanks to constant technical progress, there are now numerous digital tools in the field of lay resuscitation. There are also feedback devices for CPR for laypersons, the use of which is currently the subject of scientific debate. In order to evaluate the influence of various tools on the quality of lay resuscitation, we are planning a prospective, randomized study in a parallel group design. This study is aimed at medical laypersons between the ages of 18 and 70 who have completed a BLS course (e.g. first aid course for driver's license) within the last 10 years. All participants are asked to take part in a mannequin-based simulation scenario in a public place. As part of this simulation scenario, the BLS algorithm is to be performed (recognizing respiratory-circulatory arrest, calling for help, performing chest compressions, organizing a defibrillator). After performing the 1-minute cardiac massage, the scenario is ended. We plan to randomize into 3 groups. Group 1 will receive paper-based information material on how to perform BLS correctly. Group 2 will receive a first aid app. Group 3 will receive a small medical device (CorPatch®), which gives direct feedback on the quality of chest compressions (e.g. frequency, depth), including an accompanying app for support. The time to blood flow (defined as the succession of 5 sufficient chest compressions in this study) will be evaluated as the primary outcome. Secondarily, resuscitation management will be evaluated using a validated BLS checklist, the time to critical actions (such as time to alert the emergency services), the quality of CPR, the cognitive load of the participants and the user-friendliness of the assigned aid.

Inclusion Criteria:

• 18-70 years
• First Aid Training within the last 10 years

Exclusion Criteria:

- medical student, physician, nurse, paramedic