In-hospital cardiac arrest (IHCA) is associated with significant mortality and morbidity. 1,2 Previous studies have shown substantial variation in outcomes after IHCA across hospitals in the United States, including return of spontaneous circulation (ROSC) and survival to hospital discharge. [3][4][5][6][7][8][9][10][11][12][13][14] Moreover, hospitals vary in their ability to improve outcomes over time. 3,5 Hospital-level variation in