Changes in Relative Importance of the 5-Level Triage System, Korean Triage and Acuity Scale, for the Disposition of Emergency Patients Induced by Forced Reduction in Its Level Number: a Multi-Center Registry-based Retrospective Cohort Study

Abstract

Background The 5-level triage tool, the Korean Triage and Acuity Scale (KTAS), was developed based on the Canadian Triage and Acuity Scale and has been used for triage in all emergency medical institutions in Korea since 2016. This study evaluated the association between the decrease in level number and the change in its relative importance for disposition in the emergency department (ED). Methods Using the registry of the National Emergency Department Information System (NEDIS) ver. 3.1, data regarding consecutive emergency patients from March 2017 to October 2017 were reviewed retrospectively. Reconfiguring KTAS levels, a total of 15 multinomial logistic regression models (KTAS_0 to KTAS_14), including the KTAS, its variants, and covariates were constructed to determine significant factors affecting ED disposition. The relative importance of each model was obtained using a dominance analysis. Results A total of 79,771 patients were included in the analysis. In the model KTAS_0, the KTAS and 8 covariates were found to be significantly related to ED disposition. The KTAS and the decision maker of each ED visit, whether it was the physician or others, had the largest relative importance, 34.8% and 31.4%, respectively ( P < 0.001). In other models of KTAS variants, including 4-level, 3-level and 2-level, the rates of the KTAS decreased to 31.8% (interquartile range [IQR], 28.9–34.2), 26.4% (IQR, 23.2–31.0), and 18.7% (IQR, 7.5–24.9), respectively ( P = 0.016). On the other hand, the rates for covariates tended to be larger for smaller triage levels and so there was a significant interaction effect between the KTAS and the covariates according to the triage level ( P < 0.001). Conclusion The 5-level triage tool, the KTAS, had the largest relative importance among the predictors affecting ED disposition only at its original level. Therefore, it is recommended that no attempt should be made to reduce the number of levels in the triage tool.

Characteristics of frequent adult emergency department users

“…The KTAS was developed in 2012 and has been implemented in all Korean emergency medical centers since 2016. [ 14 , 15 ] There are 5 KTAS levels ranging from level 1, which represents a critically ill patient requiring immediate medical attention, to level 5, which represents a nonurgent patient. Patients designated as KTAS levels 1 to 3 are presumed to need urgent care.…”

Triage accuracy and causes of mistriage using the Korean Triage and Acuity Scale

“…KTAS is a five-level triage scale developed in 2012 and based on CTAS, modified to apply to the medical situation in South Korea [5, 15]. KTAS is a symptom-oriented classification tool for evaluating patients.…”

“…KTAS is a symptom-oriented classification tool for evaluating patients. After the critical first-look assessment, emergency nurses determine the triage level by evaluating the primary considerations, including vital signs, pain score, hemorrhagic disease, mechanism of injury, and secondary considerations, including blood glucose level and degree of dehydration (Fig 1) [5, 15]. The KTAS score allocated by the emergency nurses determines patient waiting time until assessment by a ED doctor and the applicable medical treatment fee (emergency, KTAS 1–3 level or non-emergency, KTAS 4–5 level) [5, 15].…”

“…A limitation of this method is that the evaluator determines the gold standard by analyzing the medical records without direct examination of the patient. In view of the increasing role played by the nursing records in legal disputes [14] and that nurse triage outcomes in Korea are directly related to the cost of emergency medical care [15], the evidence for triage decisions should be clearly documented. Therefore, evaluation of triage accuracy based on the medical records will be useful not only in assessing the accuracy of the classification of the KTAS but also in evaluating the evidence for nurse triaging decisions resulting in mistriage.…”

Prolonged Length of Stay in the Emergency Department and Increased Risk of In-Hospital Cardiac Arrest: A nationwide Population-Based Study in South Korea, 2016–2017

“…Patients with cancer included those with both solid and hematologic malignancies, without staging information. The KTAS is a reliable tool for triaging patients according to severity [ 13 ]. Patients were assigned KTAS levels of 1 to 5, with level 1 indicating the most severely ill patients, including unstable vital signs and altered mentality.…”