This document summarizes a study that used data mining techniques to explore abnormal diagnoses in emergency department triage. The study analyzed patient data from an emergency department in Taiwan to identify correlations between triage levels and diagnoses. Using hierarchical and partitioning clustering, the study established clusters of abnormal diagnosis patterns. Decision trees were also used to improve consistency in triage decisions and provide more objective triage guidelines. The goal was to apply data mining to enhance triage accuracy and patient management in emergency situations.