How do interventions in primary care or in emergency departments impact less urgent patients’ emergency care utilization? A systematic review

Health care policy in Germany focuses on restructuring ambulatory emergency care services to serve patients more efficiently. Up to 60% of patients self-refer to emergency departments (EDs), although a relevant share could be treated in primary care. This systematic review aims to determine how interventions in primary care or in emergency departments impact emergency care utilization, especially by less urgent patients self-referring to EDs. This systematic review was registered in PROSPERO in 2023. MEDLINE, the Cochrane Library, and Epistemonikos were last searched in April 2025. Reference- and cited-by-searches were conducted. RCTs or non-randomized studies with an intervention and a comparison group were included. Titles and abstracts were screened, and the quality of full texts was assessed by 2 independent reviewers. Quality assessment was conducted with the Cochrane Risk-of-Bias Tool for RCTs and with the ROBINS-I criteria for non-randomized studies. Data on study characteristics and results were extracted by one reviewer and checked by a second reviewer. The outcome of primary interest was the utilization of EDs or primary care services. Data was extracted for the following interventions: changes in the accessibility/availability of primary care physicians; new/alternative primary care services for emergency care; patient education about available emergency services; addition of primary care services to EDs; introduction of common access points for emergency ED/primary care at hospitals; and co-payments for ED attendance. Studies suggest that increasing the accessibility/availability of primary care services outside of the ED reduces ED utilization, especially by less urgent patients. The addition of primary care services to EDs may induce additional demand. The quality of the best available non-randomized evidence was low. Primary care services outside the hospital, especially out-of-hours, may keep especially low-acuity patients away from EDs. The addition of primary care services to EDs in hospitals may increase demand in hospital/ED care. Owing to the low certainty of the evidence, these findings should be interpreted with caution. Future high-quality studies should track patient pathways to monitor the origins of avoidable self-referrals to EDs as well as the quality of care these patients receive. New care models such as virtual patient consultations could be further investigated. CRD42023493308