A study involving researchers from Harvard University, Oxford University and Mayo Clinic found that a simple, data-driven triage protocol reduced emergency department length of stay by 11 minutes without compromising patient safety or requiring additional resources.

Published in the INFORMS journal Management Science, the study highlights how the research group developed an evidence-based protocol to identify patients who could safely receive care in a seated treatment area—known as a vertical processing pathway—instead of occupying a traditional emergency department bed. The study was conducted in the Public Impact Analytics Science Lab (PIAS-Lab) at Harvard in collaboration with the Mayo Clinic.

The team first analyzed nearly 50,000 emergency department visits at Mayo Clinic Arizona to develop a machine learning model that usages information collected during triage to predict whether a patient will ultimately require an emergency department bed. They then combined those predictions with mathematical models of patient flow to determine the most efficient routing strategy before translating the results into a straightforward decision tree that clinicians could implement without new software or changes to hospital IT systems.

To evaluate the approach in practice, the researchers conducted a 13-week prospective field trial involving 11,015 patients at Mayo Clinic Arizona's new emergency department.

The results demonstrated measurable improvements in efficiency:
• 11-minute (4.2%) reduction in total emergency department length of stay.
• Eight-minute (4.5%) reduction in time from arrival to clinical disposition.
• No increase in 72-hour return visits, indicating patient care quality was maintained.

"Our goal wasn't to add technology to the emergency department," said Agni Orfanoudaki, researcher at Oxford University, in a statement. "It was to give clinicians a practical, evidence-based way to decide which patients can safely receive care without occupying one of the department's limited beds."

"Our findings show that improving patient flow doesn't always require expanding capacity," said Soroush Saghafian, Ph.D., co-author of the study and professor at Harvard University. "Sometimes the greatest opportunity comes from using existing resources more intelligently."

The researchers estimate that a medium-sized emergency department treating approximately 40,000 patients annually could recover nearly 6,800 bed-hours each year—enough capacity to care for roughly 2,000 additional patients while potentially generating approximately $3 million in additional reimbursement, all without expanding facilities or increasing staffing.

The protocol relies only on information hospitals already collect during triage, including a patient's Emergency Severity Index score, presenting complaint and whether the department is operating over capacity. Because it requires no additional staff, equipment or software integration, the researchers say it could be implemented quickly in many emergency departments.