Microsoft AI Diagnostic System Achieves High Accuracy in Complex Medical Case Simulations, Study Shows

Microsoft’s artificial intelligence diagnostic system correctly solved complex medical cases in a simulation more than twice as often as generalist physicians, according to a study published Thursday in Science. Mustafa Suleyman, CEO of Microsoft AI, described the result as a step toward what he calls medical superintelligence.

The system, called MAI-DxO, uses multiple AI agents to question patients, order tests, and debate diagnoses like a panel of doctors. In simulations using complex cases from the New England Journal of Medicine, the system achieved an 83% accuracy rate. Primary care doctors and general internists working individually with reference materials reached 36% accuracy, though the study did not compare the AI against the specialists or physician teams who normally handle such complex cases.

Microsoft tested DxO with models from several labs, including OpenAI, Google, Anthropic, Meta, and DeepSeek, finding its best results paired with OpenAI’s GPT-5 and GPT-5.5. While the orchestration system cut costs and boosted performance for weaker models, its accuracy gains diminished as underlying AI models grew more powerful.

Microsoft is partnering with Beth Israel Deaconess Medical Center in Boston to evaluate DxO in real-world emergency and urgent care settings.

Suleyman stated that Microsoft is also working with Mayo Clinic