Economic evaluations in emergency medicine: a 25-year systematic review of patient-level cost-effectiveness analyses (2000-2025).

Emergency departments (EDs) face rising demand and resource constraints. Cost-effectiveness analyses (CEAs) can inform resource allocation, but patient-level CEAs in emergency care remain methodologically heterogeneous. This review aimed to identify and describe patient-level CEAs in emergency care between 2000 and 2025, appraise their methodological quality, and explore temporal trends and evidence gaps. This systematic review was reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020. PubMed/MEDLINE, Web of Science, CENTRAL, and gray literature were searched for patient-level CEAs of clinical or organizational interventions across prehospital, ED, and postemergency settings. Data were synthesized narratively across key methodological domains. Methodological quality of the economic evaluations was assessed using the quality of health economic studies (QHES) instrument. Descriptive and exploratory analyses were performed. Forty-seven studies were identified, of which 96% were conducted in EDs. Infectious diseases and ED crowding were the most addressed topics, followed by cardiovascular conditions and trauma, although a broad range of issues was covered. Studies were mainly conducted in high-income countries and evaluated organizational or diagnostic interventions. Healthcare system or hospital perspectives and short time horizons predominated. QHES scores were moderate-to-high (mean: 80.0, SD: 9.2, range: 56-96), with substantial variability and only a weak exploratory temporal trend toward higher scores. Prehospital and postemergency settings were underrepresented. Patient-level CEAs in emergency medicine are increasing, with many studies achieving high QHES scores, but remain heterogeneous in scope and methods. This review highlights the range of interventions evaluated and the methodological features relevant to interpreting economic evidence in emergency care.