OpenAI o3 Deep Research Diagnoses 18 Previously Unsolved Rare Pediatric Diseases in Study Published in NEJM AI

Researchers at Boston Children's Hospital and Harvard reanalyzed 376 de-identified unsolved cases using OpenAI's o3 Deep Research and confirmed 18 new pediatric rare-disease diagnoses after expert clinical review — a 4.8% additional diagnostic yield. The study, published in NEJM AI, found the model generated evidence-linked hypotheses for neurodevelopmental conditions, neuromuscular disorders, sudden-death cases, and early childhood psychosis that specialists had not resolved for years. The AI functioned as a secondary reader rather than an autonomous diagnostician, with all diagnoses requiring follow-up testing and clinical confirmation by physicians.