Effectiveness of nurse triage in the emergency department of an urban county hospital.

The effectiveness of patient triage by a specially trained registered nurse in the emergency department of an urban county hospital, San Francisco General Hospital, was evaluated over a three-month period. Ambulatory patients thought to have nonemergent illnesses were directed to the Walk-In Service for physician evaluation and treatment; the remainder were seen in the Emergency Service. In three months, 11,329 patients registered for care, and 4,150 (37%) were referred to the Walk-In Service. Of the 77 admitted patients, six were thought to require treatment within a few hours, 67 within hours to days, and four were considered elective admissions. There were no deaths. Error in triage was about equally divided between mistaken diagnosis and underestimated severity of illnes. The overall accuracy of triage was 98%.