Comparison of Outpatient Department-Referred and Self-Referred Patients in the Emergency Department

Background: Patients present to emergency departments (EDs) from a variety of backgrounds, which may help inform decision making. Objective: This study investigated the clinical characteristics and outcomes of outpatient department (OPD)-referred patients and self-referred patients in the ED. Methods: We selected nontrauma ED adult patients from a tertiary teaching hospital in Taiwan between August 1, 2020, and October 31, 2020. The acuity levels were determined by dichotomizing the triage classification scores. After propensity score matching, we compared the hospitalization, mortality, and length of ED stay of OPD-referred and self-referred patients. We categorized the patients into "emergency" or "urgent" subgroups according to their triage information and then analyzed the effects of different severity levels. Statistical significance was set at p < 0.05. Results: A total of 564 OPD-referred and 11,959 self-referred patients were included. After propensity score matching, the OPD-referred patients (n = 564), compared with self-referred patients (n = 564), had a higher admission rate (49.8% vs. 28.9%; p < 0.001; odds ratio [OR] 2.44). Among the emergency subgroup patients, there was no significant difference between OPD-referred patients (n = 131) and self-referred patients (n = 138) regarding the admission rate (p = 0.257) or the mortality rate (p = 0.253). Among the urgent subgroup patients, OPD-referred patients (n = 433), compared with self-referred patients (n = 426), had a significantly higher admission rate (46.0% vs. 20.2%; p < 0.001; OR 3.36), but not mortality rate (2.1% vs. 0.5%; p = 0.064). Regarding the length of ED stay, OPD-referred and self-referred patients had a significant difference only in the "urgent and discharged" subgroup (5.8 vs. 2.3 h; p < 0.001). Conclusions: OPD-referred ED patients might have more severe and complex conditions and need comprehensive care management. (c) 2023 Elsevier Inc. All rights reserved.