Delayed EHR availability of vital signs is associated with nursing shift structure.

Delayed EHR availability of vital signs may jeopardize patient safety and data integrity. In 11.4 million measurements from 26,479 encounters, median measurement-to-validation lag ranged 12-25 minutes across locations; one-third of abnormal values were delayed over an hour. Lag peaked before nursing shift changes, including in settings with device-EHR integration. These findings implicate workforce-driven workflow, rather than technical failure, as a primary barrier to real-time surveillance and health system responsiveness.