Mapping the literature on improving primary-to-secondary care referrals through the lens of the Quintuple Aim framework for healthcare improvement: a scoping review.

OBJECTIVES: To explore and map the literature on referral pathway gaps and improvement strategies in primary healthcare (PHC) to secondary healthcare (SHC) referrals, and to categorise both gaps and improvements using the Quintuple Aim framework for healthcare improvement-a model encompassing patient experience, population health, costs, provider well-being and health equity. DESIGN: Scoping review guided by Arksey and O'Malley's framework, refined by the Joanna Briggs Institute and reported following the Preferred Reporting Items for Systematic Review and Meta-Analysis extension for Scoping Reviews (PRISMA-ScR) guidelines. DATA SOURCES: PubMed, CINAHL and Scopus were searched for publications from January 2013 to May 2024. ELIGIBILITY CRITERIA: Peer-reviewed, English-language studies reporting on improvements to PHC-to-SHC referral processes. Studies were eligible if they examined referrals initiated by primary care physicians (population) addressed interventions or improvements targeting referral gaps (concept) in PHC settings (context). Studies focused exclusively on secondary care perspectives, non-English publications and those outside the 2013-2024 date range were excluded. DATA EXTRACTION AND SYNTHESIS: Data were charted using a standardised form based on a Population-Concept-Context framework. Data extraction was partially supported by the artificial intelligence-based platform Elicit, with systematic verification against source articles. Referral gaps and improvements were mapped to the five Quintuple Aim domains using structured analytical columns applied to each included study, then synthesised narratively. RESULTS: 85 studies were included. Analysis revealed recurring referral pathway gaps across five stages (patient assessment, information transfer, coordination, specialty access and feedback), negatively impacting all five Quintuple Aim domains. Eight categories of improvements were identified (eg, educational initiatives, electronic referral systems, structured templates, decision support tools). These improvements frequently enhanced referral efficiency; however, evidence of impact on provider well-being and health equity was limited. CONCLUSIONS: Referral improvements can enhance efficiency, but evidence of impact on provider well-being and health equity remains sparse. Future research should prioritise equity-focused designs and address administrative burden and resource constraints to achieve full Quintuple Aim alignment. TRIAL REGISTRATION NUMBER: Open Science Framework (https://osf.io/87htv/).