Abstract
Background: To compare outpatient department (OPD) referral patients and self-referral patients in the emergency department (ED) in terms of hospitalization, mortality, and length of stay.Methods: We collected ED patients of a tertiary teaching hospital over a 3-month period. We excluded pediatric patients and patients with certain inconsistent characteristics, such as trauma and out-of-hospital cardiac arrest, or referral from other facilities. After propensity score matching, we compared the hospitalization, mortality, and length of stay in the ED of the OPD-referral patents and self-referral patients. We categorized the patients as “emergency” or “urgency” according to their triage information and then analyzed the effects of different severity levels.Results: The OPD-referral ED patients, compared with the self-referral patients, had a higher admission rate (49.8% vs. 28.9%, p < 0.001; odds ratio [OR] = 2.44, 95% confidence intervals [CIs]: 1.91 - 3.12). Among the emergency patients, there was no significant difference regarding the admission rate (62.6% vs. 55.8%, p = 0.257) or the mortality rate (4.6% vs. 8%, p = 0.253). Among the urgent patients, the admission rate was significantly different between the OPD-referral and self-referral groups (46% vs. 20.2%, p < 0.001; OR = 3.36, 95% CIs: 2.48 - 4.55). The urgent patients who were referred from OPD tended to have a higher mortality rate (2.1% vs. 0.5%, p = 0.064). Regarding the length of ED stay, only the discharge and urgent subgroups differed according to OPD- and self-referral status (p < 0.001), with a median of 5.8 hours versus 2.3 hours.Conclusions: The OPD-referral ED patients have a higher admission rate and a longer length of stay than self-referral patients in urgent triage. The OPD-referral ED patients might have more severe and complex conditions. We should be more alert to OPD-referred patients even when they initially appear not severely ill.