Highlights: Abstract: Objective: Advanced life support (ALS) knowledge and skills decrease in as little as three months, but only a few ALS providers actually attend retraining courses. We assess the effectiveness of a 3D serious game as a new tool for frequent ALS retraining.Methods: We developed a 3D serious game for scenario-based ALS retraining. The serious game, called EMSAVE, was designed to promote self-correction while playing. We organized a retraining course in which 40 ALS providers played two cardiac arrest scenarios with EMSAVE and took a test with 38 multiple-choice questions before and after playing. We administered the same test again 3 months later to evaluate retention. Participants also rated EMSAVE and the overall retraining experience.Results: After using EMSAVE, the n….