[version 1; peer review: 2 approved]
No competing interests were disclosed.
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have documented a wide range of recruitment and retention (R&R) strategies, but the evidence base remains fragmented, outdated, and geographically uneven.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.
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).
This review will provide an updated and comprehensive assessment of R&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.
A global crisis is unfolding as the shortages in the health workforce
Primary Care Physicians (PCPs) are the cornerstone of healthcare systems, delivering first-contact, comprehensive, continuous and coordinated care.
The challenges surrounding the PCPs workforce supply–demand imbalance are complex and multidimensional: while shortages have been consistently reported across different countries,
Several factors have been identified as contributors to the PCP shortages, including increasing workload,
In 2010, the WHO issued global policy recommendations to increase access to health workers in remote and rural areas establishing a GRADE-informed framework
The COVID-19 pandemic intensified burnout and attrition and reshaped models of care, generating persistent backlogs and altering the conditions under which PCPs work,
In this context, a new, comprehensive systematic review is needed to map and appraise current recruitment and retention strategies for PCPs in high-income countries. Our goal is to deliver actionable, evidence-informed insights to policymakers and educators and to guide sustainable, context-aware solutions that bolster primary-care workforce resilience.
This protocol outlines a systematic review of quantitative evaluations of strategies to recruit and retain primary care physicians (PCPs) in high-income countries (HICs), updating the evidence base from 2015 onward to inform policy and training decisions.
The review pursues the following objectives:
Determine which strategies—policy, financial, educational/training, regulatory, organizational, and multi-component packages—are associated with improved recruitment and/or retention of PCPs in HICs. Map and compare definitions and measures of “recruitment” and “retention” used across studies and contexts, identifying points of divergence that affect comparability and synthesis. Examine the influence of health-system models (e.g., public vs private/mixed; single- vs multi-payer; gatekeeping arrangements) on the selection, implementation, and effectiveness of recruitment and retention strategies. Assess contextual modifiers—such as rurality/remote status and area-level deprivation—shaping the adoption and effectiveness of recruitment and retention strategies.
This review will adhere to PRISMA 2020
| Component | Description |
|---|---|
| Population | Primary care physicians (general practitioners, family physicians); Medical students and residents in general practice/family medicine |
| Intervention | Any intervention explicitly designed to improve recruitment and/or retention in primary care |
| Comparator | No intervention; Alternative intervention |
| Outcomes | Primary outcomes: Number/proportion of physicians recruited or retained; Duration of retention
|
| Study Design | Quantitative studies only |
This systematic review will include any quantitative studies that evaluate the impact of interventions or strategies aimed at improving the recruitment and/or retention of primary care physicians. Given the complexity and diversity of workforce interventions, a broad range of study designs will be considered eligible, including:
Randomized controlled trials (RCTs) and cluster RCTs Quasi-experimental studies, including non-randomized controlled trials Controlled before-and-after (CBA) studies Interrupted time series (ITS) analyses Observational studies, including prospective and retrospective cohort studies, case-control studies, and cross-sectional surveys that report quantitative data on relevant outcomes
Studies must report measurable outcomes related to recruitment or retention. Qualitative studies, mixed-methods studies without extractable quantitative results, opinion pieces, narrative reviews, editorials, and conference abstracts without full text will be excluded.
This systematic review will include studies involving individuals at various stages of the primary care medical career pathway. Specifically, eligible populations are:
Primary care physicians, including general practitioners, family physicians, and other generalist doctors who provide first-contact, continuous, comprehensive, and coordinated care within a primary care setting; Medical students enrolled in undergraduate medical programs with a declared or potential interest in primary care; Residents or specialty trainees undergoing postgraduate training in general practice or family medicine.
Studies focusing on healthcare professionals other than physicians (e.g., nurses, physician assistants), or on physicians not working in primary care (e.g., specialists), will be excluded.
This systematic review will include any type of strategy aimed at the recruitment and retention of primary care physicians (General Physicians, General Practitioners, Family Physicians) in high-income countries defined by OECD criteria.
Will be excluded from the review:
Strategies that do not specifically aim to address the recruitment or retention of primary care physicians or medical students. Strategies targeting healthcare professionals other than physicians (e.g., nurses, physician assistants). Strategies targeting physicians not working in primary care (e.g., specialists). Studies conducted exclusively in low- and middle-income countries, as workforce challenges and healthcare infrastructures in these settings differ significantly from those in high-income countries. Studies that do not evaluate a clearly defined intervention or strategy.
Where relevant, strategies will be compared against alternative strategies or the absence of a specific strategy. Studies with control groups, including comparisons between different interventions or between intervention and non-intervention groups, will be included when available.
The primary outcomes of interest are:
The number of primary care doctors recruited or retained, defined as the total number of Primary Care Physicians (including General Practitioners, Family Physicians, or Family Doctors) who enter or remain in primary care practice following a specific intervention. The duration of retention, measured in the number of years a physician continues to practice in a given location after a specific intervention.
Additional outcomes will be assessed where reported in the included studies. These may include:
Future career intentions of physicians, such as the expressed likelihood of entering or remaining in primary care practice. Cost-effectiveness, including the reported financial investments associated with recruitment and retention programs, and any available economic evaluations. Physician satisfaction and well-being, measured through validated instruments or self-reported assessments. Workforce stability and accessibility to primary care services, such as reductions in turnover, increases in workforce supply, or improvements in patient access to general practitioners.
| Outcome measure | Rationale |
|---|---|
| Number of Primary Care Physicians recruited or retained | Represents the core metric of workforce growth or stabilization following an intervention; directly reflects the primary objective of recruitment and retention strategies. |
| Duration of retention (years in practice post-intervention) | Measures long-term impact and sustainability of interventions; captures whether strategies lead to meaningful improvements in physician workforce continuity. |
| Future career intentions | Assesses anticipated workforce behavior, providing predictive insight into long-term retention trends and physician satisfaction. |
| Cost-effectiveness of strategies | Essential for policy and planning; allows comparison of interventions not only on outcomes but also on resource efficiency and scalability. |
| Physician satisfaction and well-being | Indicates perceived impact of interventions; correlates with retention and performance; essential to understand intervention impact beyond numerical workforce data. |
| Workforce stability and accessibility to primary care | Reflects system-level outcomes; helps evaluate whether interventions contribute to equitable service delivery, especially in underserved or rural areas. |
No language restrictions will be applied. For articles published in languages other than English, translation tools; any issues related to translation will be transparently reported in a specific appendix.
We will search the following electronic databases: MEDLINE (via PubMed), Embase and CENTRAL. The search will cover all literature from February 2015 to the final search date, with no language restrictions. A draft of the search strategy for Embase is reported below. To ensure transparency and reproducibility, the full search strategies will be made publicly available on OSF as Extended Data (DOI
(‘general practitioner’/exp OR ‘general practitioner’ OR ‘family physician’/exp OR ‘family physician’ OR ‘general practice’/exp OR ‘general practice’ OR ‘general practitioner*’:ti OR ‘general practitioner*’:ab OR ‘family physician*’:ti OR ‘family physician*’:ab OR ‘family doctor*’:ti OR ‘family doctor*’:ab OR ‘primary care physician*’:ti OR ‘primary care physician*’:ab OR ‘primary care doctor*’:ti OR ‘primary care doctor*’:ab OR ‘primary care provider*’:ti OR ‘primary care provider*’:ab)
AND
(‘personnel management’/exp OR ‘personnel management’ OR ‘physician engagement’/exp OR ‘physician engagement’ OR ‘retention time’/exp OR ‘retention time’ OR recruitment*:ti OR recruitment*:ab OR retention*:ti OR retention*:ab OR retain*:ti OR retain*:ab OR ‘workforce planning’:ti OR ‘workforce planning’:ab OR ‘physician* allocation’:ti OR ‘physician* allocation’:ab OR ‘workforce retention’:ti OR “workforce retention’:ab OR “workforce stability’:ti OR “workforce stability’:ab OR “physician retention’:ti OR “physician retention’:ab OR “workplace engagement’:ti OR “workplace engagement’:ab) AND [humans]/lim AND [2015-2025]/py
The strategy will include both controlled vocabulary terms (e.g., MeSH, Emtree) and free-text keywords related to primary care physicians, recruitment, retention, and high-income countries.
The following bibliographic databases will be searched: MEDLINE (via PubMed), Embase (via
Reference lists of all included studies will be hand-searched to identify additional relevant articles not captured through database searching. Duplicate records will be removed in Rayyan. Zotero (v. 7.0.30) will be used as the citation manager for reference handling and manuscript preparation
Records retrieved from each database will be exported and imported into Zotero (v. 7.0.30) for reference management. De-duplication will be performed in Rayyan, after which the de-duplicated library will be used for screening and to maintain an audit trail of decisions.
Titles and abstracts will be independently screened by two reviewers (F.C. and B.B.) against the predefined eligibility criteria. Full texts of all studies deemed potentially eligible, or for which there is any uncertainty, will be retrieved and assessed in full.
Any disagreements at the title/abstract or full-text screening stages will be resolved through discussion. If consensus cannot be reached, a third reviewer (D.P.) will be consulted.
The full selection process will be documented using the PRISMA 2020 flow diagram, including the number of records identified, included, and excluded at each phase, with reasons for exclusion clearly reported.
Companion or duplicate publications will be identified through comparison of author lists, sample characteristics, and intervention descriptions, and will be merged or excluded as appropriate to avoid double-counting of data. In cases of missing or unclear data, corresponding authors will be contacted by email (up to three attempts) to request clarification or supplementary information.
Data will be extracted using a standardised form developed and piloted by the review team. Extracted items will include: study design, country, setting, population, intervention characteristics, comparator (if applicable), outcomes related to recruitment or retention, and key findings. Two reviewers will independently extract data for all included studies; disagreements will be resolved by consensus or, if needed, by a third reviewer (D.P.).
Risk of bias will be assessed using:
The Quality Assessment Tools for Case-Control, Cohort, and Cross-Sectional Studies of the National Institute of Health (USA) will be used. The Quality Assessment Tools for controlled Studies of the National Institute of Health (USA) will be used.
Data will be assessed independently by at least two people with a process to resolve differences.
Risk of bias will be assessed at the study level. Risk-of-bias judgements will be used to inform about the certainty of evidence assessment.
Given the expected heterogeneity in study designs, interventions, and outcome definitions, findings will primarily be synthesised narratively. We will use a thematic synthesis to categorise the evidence according to the types of recruitment and retention strategies identified, supported by evidence tables and summary matrices. Where helpful, studies will be grouped by: author/year; country; study design; sample characteristics and population/setting (e.g., early-career vs experienced GPs; rural vs urban); healthcare system model (e.g., publicly funded, mixed, private); intervention category (e.g., financial incentives, educational programmes, workforce policies); outcome measure; and results. Quantitative findings will be summarised descriptively (absolute numbers, percentages, and effect estimates as reported). Because substantial variability in methods and outcomes is anticipated, meta-analysis will be considered only when a sufficient number of studies report comparable outcomes and effect estimates can be pooled appropriately; otherwise, results will be presented through narrative synthesis with descriptive statistics.
If quantitative synthesis is feasible, we will conduct a random-effects meta-analysis, selecting effect measures appropriate to the outcome type (RR/OR or MD/SMD). Where needed, we will convert reported statistics to a common effect metric when sufficient information is available, and we will report 95% confidence intervals. Heterogeneity will be assessed using I 2; where pooling is not appropriate, findings will be synthesised narratively. Subgroup and sensitivity analyses will be conducted only if feasible, focusing on the prespecified grouping variables (e.g., career stage, setting, intervention category); meta-regression is not planned.
Assessment of reporting biases is not planned due to the anticipated heterogeneity and small numbers of studies per outcome. To mitigate potential bias arising from missing or selectively reported results, we will search multiple databases without language restrictions, document the selection process with a PRISMA 2020 flow diagram, extract and report funding sources and authors’ conflicts of interest, and discuss any concerns in the Limitations.
The overall certainty (strength) of the body of evidence will be appraised narratively, as prespecified in the PROSPERO record, using criteria aligned with the GRADE domains. For each primary outcome, we will consider: (i) risk of bias of contributing studies (based on the NIH quality assessment tools), (ii) consistency of findings across studies, (iii) precision/imprecision of effect estimates or descriptive summaries, and (iv) directness/applicability to the review question and settings. A formal assessment of publication bias is not planned; any concerns related to missing or selectively reported results will be discussed narratively. Certainty judgements will be summarised in the text and, where helpful, presented in a descriptive summary table (e.g., a narrative ‘Summary of Findings’ table).
Any important amendments to this protocol will be documented in the PROSPERO record, including the date, description, and rationale for each change.
This review will examine recruitment and retention (R&R) strategies for primary care physicians as active components of workforce change, clarifying how they are designed, implemented, and reported—and how they influence career choice, practice location, and tenure in high-income settings. By analysing intervention logic alongside outcomes, and by mapping definitions of “recruitment” and “retention,” the review will identify which elements (e.g., incentives, training pathways, workload redesign, professional support) drive effects, and under what system (financing, gatekeeping) and contextual (rurality, deprivation) conditions they perform best. A structured narrative synthesis will organise findings by strategy type and career stage, translating quantitative results into workforce-relevant metrics to support planning. The resulting evidence will guide the design of more targeted, scalable, and context-sensitive packages, distinguishing core components from adaptable features, and highlighting implementation considerations (acceptability, feasibility, costs) and equity impacts where available. Ultimately, the review aims to inform policy, education, and service planning by providing practical guidance on assembling coherent R&R strategies that strengthen and stabilize the primary-care workforce.
Results of this review will be disseminated through peer-reviewed publications, conference presentations.
Not applicable. This study does not involve human participants or primary data collection.
To ensure transparency and reproducibility, the full search strategies will be made publicly available on OSF as Extended Data (DOI
No data are associated with this article.
Open Science Framework (OSF):
The project contains the following extended data:
search strategy 12 25.pdf (full database search strategies: MEDLINE/PubMed, Embase, CENTRAL). Prisma P Checklist.pdf (completed PRISMA-P 2015 checklist).
Data are available under the terms of the
This protocol follows the PRISMA-P 2015 statement. The completed PRISMA-P checklist is available on OSF as Extended Data (DOI
The authors would like to thank colleagues from the Department of Public Health and Primary Care, University of Cagliari, and the Wolfson Institute of Population Health for their input on the preliminary design of this review. The authors acknowledge support from the University of Cagliari under Open Access funding call for the publication of this work.
This manuscript presents a protocol for an updated systematic review of recruitment and retention strategies for primary care physicians in high-income countries. The topic is timely and important, given persistent primary care workforce shortages, unequal geographical distribution of physicians, increasing demand from ageing and multimorbidity, and changes in care delivery following COVID-19.
The rationale is clear and well supported. The authors effectively explain why an updated synthesis is needed, particularly because previous reviews are now dated, geographically uneven, and may not fully reflect recent workforce pressures, digital transformation, or post-pandemic working conditions. The objectives are relevant and appropriately aligned with the proposed review question.
The protocol is generally well designed. It is registered in PROSPERO, follows PRISMA guidance, uses broad but justified eligibility criteria, and includes independent screening, extraction, and risk-of-bias assessment by two reviewers. The planned narrative synthesis is appropriate given the expected heterogeneity in interventions, outcomes, and study designs. The inclusion of contextual modifiers such as rurality, deprivation, and health-system model is a strength, as recruitment and retention interventions are highly context dependent.
I have several recommendations that could further strengthen the protocol:
First, the authors could provide clearer operational definitions of “recruitment” and “retention.” Although the protocol states that definitions will be mapped across studies, pre-specifying categories or minimum criteria would improve consistency during screening, extraction, and synthesis.
Second, the authors should clarify the criteria for deciding whether meta-analysis is feasible. The protocol currently states that meta-analysis will be considered where outcomes are sufficiently comparable, but more detail would be useful, for example regarding minimum numbers of studies, acceptable outcome similarity, and how heterogeneity will influence decisions.
Third, the authors may wish to include a simple conceptual framework linking intervention categories, mechanisms of action, intermediate outcomes, and final workforce outcomes. This would help readers understand how financial, educational, regulatory, organisational, and multi-component strategies are expected to influence recruitment and retention.
Fourth, the planned assessment of certainty of evidence could be described more explicitly. The protocol mentions GRADE-aligned domains, but a more structured approach, even if narrative rather than fully formal GRADE, would improve transparency.
Finally, given the broad scope of the review, the authors could explain how they will prioritise findings if the evidence base is too heterogeneous or extensive. For example, they could pre-specify that primary outcomes, physician-level retention/recruitment outcomes, or higher-quality comparative studies will receive greater interpretive weight.
I was not able to assess the underlying results or conclusions of the planned systematic review, as this is a protocol and no review findings are yet available. I also could not assess the performance of the final search strategy across all databases beyond the information provided in the manuscript and linked supplementary materials.
Yes. The rationale is well developed and the objectives are clearly stated, relevant, and aligned with the research question.
Yes. A systematic review is appropriate, and the inclusion of diverse quantitative study designs is justified by the nature of workforce interventions.
Yes, with minor reservations. The eligibility criteria, databases, screening process, data extraction, risk-of-bias assessment, and synthesis approach are described in sufficient detail. Replicability would be improved by more detail on meta-analysis feasibility criteria, operational outcome definitions, and the structured application of certainty-of-evidence assessment.
Not applicable. This is a study protocol and no dataset has yet been generated.
The protocol is scientifically sound and suitable for indexing, but the minor methodological clarifications above would improve transparency, reproducibility, and usefulness of the eventual review.
I invite the authors to include the following statement in the manuscript:
The authors should clarify that any amendments to the protocol, including changes to eligibility criteria, outcomes, search strategy, or synthesis methods, will be documented transparently in PROSPERO and reported in the final review, with dates and rationales for each amendment.
Is the study design appropriate for the research question?
Yes
Is the rationale for, and objectives of, the study clearly described?
Yes
Are sufficient details of the methods provided to allow replication by others?
Yes
Are the datasets clearly presented in a useable and accessible format?
Not applicable
Reviewer Expertise:
Expert in research in primary care
I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.
This manuscript presents a protocol for a systematic review aiming to update the evidence on recruitment and retention (R&R) strategies for primary care physicians (PCPs) in high-income countries.
The authors justify the need for this work based on persistent and worsening global shortages of PCPs, increasing demand due to population ageing and multimorbidity, limitations of existing evidence (fragmented, outdated, geographically uneven) and system-level changes (COVID-19, digital health, AI)
The planned review will follow PRISMA 2020 guidelines and has been registered in PROSPERO. It will include quantitative studies (2015 onward) from MEDLINE, Embase, and CENTRAL and will evaluate interventions targeting recruitment and/or retention. The review will focus on outcomes such as: Number of physicians recruited/retained, duration of retention, career intentions, satisfaction, cost-effectiveness, and system-level outcomes
The methodology includes: Dual independent screening and extraction, risk of bias assessment using NIH tools, primarily narrative synthesis, with meta-analysis if feasible and consideration of contextual factors (e.g., rurality, health system models)
The study aims to produce policy-relevant, actionable insights for workforce planning.
Assessment: YES
The rationale is clear, well-structured, and compelling. It integrates epidemiological, health system, and policy arguments. It explicitly identifies gaps in previous reviews (e.g., outdated evidence, lack of contextualisation).
The objectives are clearly stated, structured into four distinct and relevant aims, directly aligned with the research problem
Assessment: YES
The choice of a systematic review is fully appropriate for the research question.
The design is methodologically sound because it follows established standards (PRISMA, PROSPERO), it includes a broad range of quantitative designs, which is justified given the complexity of workforce interventions and the expected lack of RCTs in this field.
Clarify decision rules for meta-analysis feasibility (currently somewhat vague)
Consider explicitly stating how heterogeneity thresholds (e.g., I²) will influence decisions
Assessment: YES
The methods are described in sufficient detail to allow replication.
Key elements supporting reproducibility: Clear eligibility criteria (Population, Intervention, Outcomes, Study design), explicit inclusion/exclusion criteria, detailed search strategy (example provided), transparent screening and selection process (dual reviewers, conflict resolution), defined data extraction variables, risk of bias tools specified, planned synthesis methods described.
The inclusion of OSF repository and PRISMA-P checklist further strengthens transparency.
Provide more detail on: Data extraction form (template or variables list in supplement), handling of missing data and unclear reporting and clarify whether calibration exercises will be conducted among reviewers
These are improvements, not requirements for scientific validity.
These do not affect scientific soundness, but could improve clarity and impact.
The manuscript would benefit from improved conceptual clarity through the inclusion of a clearer framework explicitly linking intervention types, their underlying mechanisms of action, and the expected outcomes. While these elements are all present in the protocol, they are not fully integrated into a single conceptual model. Making these relationships more explicit would strengthen the interpretability of the future synthesis and help readers better understand how different strategies are expected to influence recruitment and retention outcomes across contexts.
Regarding outcome definitions, although the manuscript clearly lists primary and secondary outcomes, further standardisation would enhance consistency. In particular, key concepts such as “recruitment” and “retention” may vary substantially across studies in terms of definition and measurement. The authors already acknowledge this issue and plan to map definitions across studies, which is a notable strength. However, the protocol could be further improved by pre-specifying operational definitions or categorisation frameworks in advance, thereby facilitating more structured comparisons and synthesis.
The scope of the review is appropriately ambitious but may raise feasibility challenges. The inclusion of multiple study designs, a wide range of intervention types, and numerous outcomes is justified given the complexity of workforce interventions; however, this breadth is likely to result in substantial heterogeneity. To address this, the authors should clarify how prioritisation will be managed if the evidence base proves too broad or heterogeneous to synthesise meaningfully. For example, outlining criteria for focusing on specific intervention categories, outcomes, or study designs would strengthen the methodological clarity.
In terms of bias and certainty of evidence, the planned use of NIH quality assessment tools is appropriate and aligned with the inclusion of diverse study designs. However, the approach to assessing the overall certainty of evidence using GRADE is described only narratively. The protocol would benefit from a more structured application of GRADE, even if simplified, to ensure transparency and consistency in evaluating the strength of the evidence across outcomes.
No issues have been identified that must be addressed to ensure the scientific soundness of the study. Overall, the protocol is methodologically robust and suitable for indexing in its current form.
In conclusion, this is a scientifically sound protocol of high methodological quality. It addresses an important and timely topic, demonstrates strong methodological rigour, and adheres to best practices in transparency and reproducibility. The manuscript is well-designed and clearly reported, and the proposed review has the potential to make a meaningful contribution to the field.
Final verdict: the manuscript is acceptable as it stands, with only minor improvements suggested.
Is the study design appropriate for the research question?
Yes
Is the rationale for, and objectives of, the study clearly described?
Yes
Are sufficient details of the methods provided to allow replication by others?
Yes
Are the datasets clearly presented in a useable and accessible format?
Not applicable
Reviewer Expertise:
Healthcare services research. Multimorbidity.
I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.