The quality of cardiopulmonary resuscitation (CPR) has been identified as an important determinants for patient survival, yet many studies revealed poor CPR guidelines compliance in real-life practice for both health care providers and lay persons. Common shortcomings identified include an insufficient number of chest compression, too rapid lung inflations, and too much hands-off time. The poor quality of CPR is associated with lower survival rate. Besides, some other problems could be found during resuscitation, such as prolonged intubation time, delayed first shock delivery or unsteady drug delivery interval. These problems can't be blamed on the only person but the teamwork. Certain measurements could improve the performance of the resuscitation team, such as audio prompt or checklist.

Methods proposed and improvised to improve the quality of CPR have included CPR assisted devices, automatic driven devices or audio prompt system. However, some of these methods are hardly incorporate with the original resuscitation process since it could be an extra workload. Therefore, the investigators try to provide an digitized checklist combined with visual and audio alarming system, which could not only minimize the workload of chart recording but also remind the team to perform essential procedures in time.

Information gained from a video-recording evaluation system had been employed to improve the resuscitation skills. The improvement of resuscitation quality also could be found through video-recording after certain intervention. It can also avoid the interference of the resuscitation and find out other harmful factors to CPR quality.

Inclusion Criteria:

• Out-of-Hospital cardiac arrest patient present to NTUH ED
• Age > 18 years old
• E-checklist system applied

Exclusion Criteria:

• E-Checklist system not applied
• Video not been recorded

Emergency Department patient Out-of-Hospital cardiac arrest patient receive CPR in NTUH Emergency Department Age > 18 years old