Medical Emergency Triage and Treatment System (METTS): a new protocol in primary triage and secondary priority decision in emergency medicine.

BACKGROUND In many Emergency Department (ED) triage scoring systems, vital signs are not included as an assessment parameter. OBJECTIVES To evaluate the validity of a new protocol for Emergency Medicine in a large cohort of patients referred to in-hospital care. METHODS From January 1 to June 30, 2006, 22,934 patients were admitted to the ED at Sahlgrenska University Hospital. Of those, 8695 were referred to in-hospital care and included in the study. A new five-level triage tool, combining vital signs, symptoms, and signs in the triage decision, was used. A small control of the inter-rater disagreement was also performed in 132 parallel, single-blinded observations. RESULTS Fifty percent of the patients were admitted by ambulance and the other 50% by walk-in. Hospital stay was significantly (p < 0.001) longer in those admitted by ambulance (9.3 ± 14 days) as compared with walk-in patients (6.2 ± 10 days). In-hospital mortality incidence was higher (8.1%) in patients admitted by ambulance, as compared with walk-in patients (2.4%). Hospital stay and in-hospital mortality increased with higher level of priority. In the highest priority groups, 32-53% of the patients were downgraded to a lower priority level after primary treatment. CONCLUSION In the present study, the METTS protocol was shown to be a reliable triage method and a sensitive tool for secondary re-evaluation of the patient in the ED.