Physicians shortage in primary care: a protocol for updating a systematic review of recruitment and retention strategies

<ns3:p> Background The global shortage of primary care physicians (PCPs) poses a critical threat to healthcare accessibility and system performance in high-income countries. Previous reviews have documented a wide range of recruitment and retention (R&amp;R) strategies, but the evidence base remains fragmented, outdated, and geographically uneven. In light of demographic transitions, the increasing burden of multimorbidity, and evolving models of care accelerated by the COVID-19 pandemic, an updated synthesis is needed to guide sustainable and context-sensitive workforce policies. Methods This systematic review will follow PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 guidelines and is registered with PROSPERO (International Prospective Register of Systematic Reviews) (CRD420251008508). MEDLINE (via PubMed), Embase, and CENTRAL (Cochrane Central Register of Controlled Trials), will be searched for quantitative studies published from February 2015 onward, without language restrictions. Eligible studies will evaluate interventions designed to improve the recruitment and/or retention of PCPs, medical students, or residents in high-income countries. Primary outcomes will include the number of physicians recruited or retained and the duration of retention. Secondary outcomes will cover career intentions, cost-effectiveness, physician satisfaction and well-being, and workforce stability. Two reviewers will independently conduct study selection, data extraction, and risk of bias assessment using validated NIH (National Institutes of Health) quality assessment tools. Findings will be synthesized narratively, with thematic grouping by intervention type, career stage, and contextual factors (e.g., rurality, health system model). Discussion This review will provide an updated and comprehensive assessment of R&amp;R strategies for PCPs in high-income countries. By examining intervention logic, outcomes, and contextual modifiers, it will identify which approaches are most effective under specific conditions. The results aim to inform policymakers, educators, and workforce planners in designing targeted, scalable, and context-sensitive strategies to strengthen primary care workforce resilience. <ns3:bold>Systematic Review Registration</ns3:bold> : PROSPERO registration number: CRD420251008508. </ns3:p>