What the research found
Researchers compared 198,178 emergency department encounters across four Mass General Brigham hospitals between January and September 2025: 87.7% with no scribe, 4.3% using an ambient AI scribe and 8.0% using a human scribe. Ambient AI reduced adjusted median documentation time by 1.6 minutes per note and human scribes by roughly double that, but total work RVUs per shift hour did not differ between the groups. Clinicians interviewed by STAT described real benefits the study could not measure — less cognitive load, more teaching, notes finished within 24 hours rather than 72 — while the study's own co-author was candid that it is an open question where the saved time actually goes.
The most widely adopted clinical AI tool in the country delivered exactly what it promised and still moved none of the numbers patients feel, because the constraint was never documentation — a reminder to buy AI against a named bottleneck rather than against a category.