Effectiveness of Five-Level Prehospital Taiwan Triage and Acuity Scale (TTAS-PH) in Emergency Medical Services for Patient Outcome Prediction: A Retrospective Cohort Study.

Male gender, older age, and higher TTAS-PH acuity levels (Levels 1 and 2) were significantly associated with worse emergency department outcomes and longer emergency department LOS.

TTAS-PH Level 1 patients faced drastically elevated risks of death (OR=83.9); while they represented only 10.72% of the cohort, they accounted for 79.59% of all emergency department deaths.

Notably, a discrepancy was observed in high-acuity (Levels 1-2) classification between the prehospital TTAS-PH (43%) and the in-hospital TTAS (8.7%).