The impact of primary care funding on health inequalities: an umbrella review

Background: The funding of primary care is subject to intense debate internationally. Three main funding models predominate: capitation, pay-for-performance, and fee-for-service. A number of systematic reviews regarding the effect of primary care funding structures have been published, but not synthesized through an equity lens. Given the urgent need for evaluating funding models and addressing inequalities, a reliable, synthesized evidence base concerning the effects of funding on inequalities is imperative.Aims: This umbrella review aims to systematically evaluate all systematic reviews available on the effect of different primary care funding models in high-income countries on inequalities in funding, access, outcomes, or experience from inception until 2024.Methods: Three databases (MEDLINE, EMBASE, Cochrane) and a machine learning living evidence map were searched. Abstracts and titles were double screened, before two authors independently screened full texts, extracted data, and performed quality assessments utilizing the AMSTAR2 tool.Findings: The search identified 2480 unique articles, of which 14 were included in the final review. Only one review compared reimbursement systems; capitation systems were more equitable between ethnic groups compared to pay-for-performance in terms of primary care access, continuity, and quality. Twelve reviews reviewed the impact of the introduction of pay-for-performance models, predominantly focusing on the Quality and Outcomes Framework (QOF) in the UK. Synthesized findings suggest that QOF's introduction coincided with reduced socioeconomic health inequalities in the UK overall, but not in Scotland. Overall, inequalities in age narrowed, but inequalities measured by sex widened. One review found evidence that targeting funding for minority groups, with poorer health, was effective. A further review found that introducing privately provided general practices in Sweden and allowing patients to choose these over public-owned options generally benefitted those with higher income and lower health needs. We identify a range of gaps in the literature, which should inform future research.