Comparison of prehospital triage and five-level triage system at the emergency department

There is lack of scientific evidence regarding the effectiveness of prehospital triage systems. This study compared the two-level Taiwan Prehospital Triage System (TPTS) with the five-level Taiwan Triage and Acuity Scale (TTAS) at ED arrival regarding the prediction of patient outcomes and the utilisation of medical resources.

This was a retrospective cohort study. Adult patients transported via the emergency medical service (EMS), who arrived at the ED of a medical centre in northern Taiwan during the study period were enrolled. TTAS acuity levels 1-2 were considered comparable to the designation of 'emergent' by the prehospital TPTS system. The outcomes were analysed by comparing TPTS and TTAS by acuity levels.

Among 4430 enrolled patients, 25.2% and 74.8% were classified as emergent and non-emergent by TPTS; 44.1% and 55.9% were classified as levels 1-2 and levels 3-5 by TTAS. Of the TPTS emergent patients, 15.2% were classified as TTAS levels 3-5, whereas 30.4% of TPTS non-emergent transports were classified as TTAS levels 1-2 at the ED. TTAS levels 1-2 showed better predictability than TPTS emergent level for hospitalisation rate with a sensitivity of 70.3% (95% CI 68.3% to 72.2%) versus 41.1% (95% CI 39.0% to 43.2%), and a negative predictive value of 74.8% (95% CI 73.4% to 76.0%) versus 62.6% (95% CI 61.7% to 63.5%).

The current prehospital triage system is insufficient and inappropriate in classifying patients transported to the ED. The present study offers supporting evidence for the introduction of a five-level triage system to prehospital EMS systems.