How NLP Methods Allow Quality Assurance on a Large Scale. Corti’s call center analytics solution allows emergency service providers to review 100% of the received calls instead of 1-2% as would be attainable with manual reviews. This quality assurance process effectively improves patient’s safety by ensuring best practices and protocol adherence in emergency calls. The automatic assessment of these calls requires to track key interventions as well as implied or obvious information. The respective NLP methods and models to extract all relevant details will be the focus of this presentation. Additionally, we discuss challenges we faced along the way and how they are solved.