Microsoft Diagnostic AI Outperforms Generalist Physicians in Science Study

Microsoft’s MAI-DxO diagnostic system outperformed participating generalist physicians on complex diagnostic cases in a peer-reviewed study published October 22, 2026 in Science, which reported 83.2% accuracy for the system on New England Journal of Medicine case records against 36.1% for physicians using reference resources.

The study, “Sequential diagnosis with language models,” appears in Science Volume 394, Issue 6822, pages 423–428; it was received April 4, 2026 and accepted August 10, 2026. All 15 authors are Microsoft employees, and the list includes Microsoft AI chief executive Mustafa Suleyman alongside Dominic King and Eric Horvitz. In a same-day announcement, Microsoft said the work “is published today in Science” in the journal’s “AI in Medicine” issue.

A Benchmark Built Around Step-by-Step Diagnosis

The paper introduces the Sequential Diagnosis Benchmark, or SDBench, which converts 304 New England Journal of Medicine…