PROJECT SUMMARY This application is in response to PAR-14-007, “Secondary Dataset Analysis in Heart, Lung, and Blood Diseases and Sleep Disorders.” The full title of the proposal is “Extensions of an Automated Algorithm to Examine CPR Compliance on and off Study.” Out of hospital cardiac arrest remains a major health problem with prehospital care and quality cardiopulmonary resuscitation (CPR) being key factors impacting survival. Prehospital emergency agencies that utilize process improvement strategies to evaluate care delivery and modify systems/procedures to achieve set standards provide better care and have better outcomes. A previously developed algorithm was used to classify care provided as either continuous chest compressions (CCC) or interrupted chest compressions (ICC). Use of such a tool to determine compliance with local CPR standard of care during non-trial phases is important. Automation of this step supports process improvement and better outcomes in the setting of limited resources. The purpose of this study is to acquire knowledge about prehospital emergency care through the processing and analysis of chest compression data obtained from electrocardiogram (EGC) files. The study will use existing cardiac arrest registry data collected by the Resuscitation Outcomes Consortium. Results will inform agencies of CPR quality and compliance to local standard of care when not part of a closely monitored clinical trial. The primary study aim is to use an algorithm based on three metrics (chest compression fraction, compression segment length and pauses per minute) to classify CPR strategy and then determine compliance with local CPR standard of care. Secondary aims of the study are to examine disparities in minorities and other important subgroups; to extend the algorithm to account for advanced interventions such as intubation and drug administration; to review CPR that was not classified as either strategy; and to determine the feasibility of a pragmatic data extraction process. Data exist as part of the Resuscitation Outcomes Consortium (ROC) out-of-hospital cardiac arrest registry. This study includes investigators at the University of Washington who were members of the ROC Data Coordinating Center. They have both the analytical and clinical expertise to lead such a study.