Interventions to reduce emergency department overcrowding and their effects on patient outcomes: a mixed-methods systematic review and meta-analysis

Overcrowding in emergency departments (EDs) leads to inadequate patient outcomes and increased operational costs. These complications contribute to heightened stress on healthcare systems thus, effective methods to reduce ED overcrowding are necessary to improve patient flow and overall care quality. This mixed-method systematic review and meta-analysis evaluates the effectiveness of interventions such as Fast-Track, Team Triage, and Point-Of-Care Testing (POCT) in reducing ED overcrowding and improving patient flow metrics, including ED length of stay (LOS), wait times, and discharge times, to provide evidence-based recommendations for policy and practice in emergency healthcare. This review complies with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Three databases (PubMed, ScienceDirect and Google Scholar) were systematically searched for studies published between 2015 and 2025 assessing interventions to reduce ED overcrowding. A structured risk-of-bias assessment (RoB 2, ROBINS-I, JBI, MMAT) indicated overall acceptable methodological quality, with expected limitations related to non-randomized designs and limited blinding. Mean LOS was pooled using random-effects meta-analysis in RevMan, with heterogeneity assessed and secondary outcomes summarized narratively. This study is registered with the International Prospective Register of Systematic Reviews (PROSPERO 2025: CRD42025634351). This review included 15 studies, 6 eligible for meta-analysis. Fast-Track significantly reduced ED length of stay (MD = − 20.89 min; 95% CI: − 37.05 to − 4.33; p = 0.01). POCT (MD = − 65.50 min; 95% CI: − 137.54 to 6.53; p = 0.07) and Team Triage (MD = − 46.11 min; 95% CI: − 120.59 to 28.38; p = 0.23) demonstrated variable reductions in ED LOS, with pooled effects influenced by substantial between-study heterogeneity. All analyses exhibited significant heterogeneity. Qualitative synthesis further suggested improvements in waiting times, patient throughput, and departmental efficiency. Our findings highlight the importance of targeted interventions to alleviate ED overcrowding; Fast-Track showed consistent effectiveness, while POCT and Team Triage showed variable and, often context-dependent effects. These findings offer practical and evidence-based strategies to support ED flow improvements, though further high-quality research is needed.