Mass General Brigham deployed an internal AI screening tool called RECTIFIER, which reads patient medical records to automatically identify patients who are eligible for clinical trials, and has expanded this to over 20 active use cases across the health system. In December 2025, the health system spun out a separate company called AIwithCare to commercialize this technology.

RECTIFIER (RAG-Enabled Clinical Trial Infrastructure for Inclusion Exclusion Review) uses retrieval-augmented generation (RAG), a technique combining large language model reasoning with real-time document retrieval, to screen patients' electronic health records — including free-text clinical notes, diagnoses, medications, and lab values — against clinical trial eligibility criteria. A randomized controlled trial of nearly 4,500 patients published in JAMA in 2025 showed enrollment rates nearly double those achieved by traditional manual screening. As of late 2025, more than 30 teams within Mass General Brigham were using the tool across cardiology, oncology, gastroenterology, neurology, pathology, and psychiatry. The spinout company AIwithCare plans to offer the platform to other health systems via the AIwithCare Studio product.