Abstract
INTRODUCTION: Prolonged ambulance response times and unacceptable emergency department (ED) wait times are significant challenges in urgent and emergency care systems associated with patient harm. This scoping review aimed to evaluate the evidence base for 10 urgent and emergency care high-impact initiatives identified by the National Health Service (NHS) England. METHODS: A two-stage approach was employed. First, a comprehensive search for reviews (2018-2023) was conducted across PubMed, Epistemonikos and Google Scholar. Additionally, full-text searches using Google Scholar were performed for studies related to the key outcomes. In the absence of sufficient review-level evidence, relevant available primary research studies were identified through targeted MEDLINE and HMIC searches. Relevant reviews and studies were mapped to the 10 high-impact initiatives. Reviewers worked in pairs or singly to identify studies, extract, tabulate and summarise data. RESULTS: The search yielded 20 771 citations, with 48 reviews meeting the inclusion criteria across 10 sections. In the absence of substantive review-level evidence for the key outcomes, primary research studies were also sought for seven of the 10 initiatives. Evidence for interventions improving ambulance response times was generally scarce. ED wait times were commonly studied using ED length of stay, with some evidence that same day emergency care, acute frailty units, care transfer hubs and some in-patient flow interventions might reduce direct and indirect measures of wait times. Proximal evidence existed for initiatives such as urgent community response, virtual hospitals/hospital at home and inpatient flow interventions (involving flow coordinators), which did not typically evaluate the NHS England outcomes of interest. CONCLUSIONS: Effective interventions were often only identifiable as components within the NHS England 10 high-impact initiative groupings. The evidence base remains limited, with substantial heterogeneity in urgent and emergency care initiatives, metrics and reporting across different studies and settings. Future research should focus on well-defined interventions while remaining sensitive to local context.