Correlations between modified early warning scores in emergency departments and predictions of prognosis in South Korea

We explored whether modified early warning scores (MEWS) could be used as a tool for triage in pre-hospital settings by comparing MEWS with patient triage on arrival to the emergency department (ED) and prognosis. Adult patients (>= 20 years old) admitted to EDs between 2016 and 2018 were enrolled from National Emergency Department Information System data in this retrospective study. A total of 8,609,955 participants were included in the analysis. EDMEWS of the dead (4.74 +/- 2.51) was higher than that of admitted (1.86 +/- 1.72) and discharged patients (1.18 +/- 1.15) (p < 0.001). In admitted patients, non-survivors had higher EDMEWS than survivors (p < 0.001), and as the level of the Korean Triage and Acquisition Scale was severe, EDMEWS increased (p < 0.001) accordingly in these patients. EDMEWS had an adjusted hazard ratio (HR) of 1.164 (95% confidence interval: 1.135 +/- 1.194) for mortality (p < 0.001). When an EDMEWS of 0 was used as a reference value, the HR increased with an increase in the EDMEWS. As EDMEWS increased from 1 to 7+, HR also increased from 1.115 to 2.508. EDMEWS has a positive correlation with mortality and admission rates in EDs. Moreover, admitted patients with higher EDMEWS had a longer duration of hospitalization and they had a higher mortality rate compared to patients with lower EDMEWS. MEWS can be a useful tool to provide evidence to support decision-making processes involving transportation to the ED and selection of the appropriate level of ED for pre-hospital EMS and long-term care facilities.