General practitioners are critical for realizing the safety-net function of the primary healthcare system; however, there are regional disparities in their resource allocation. Existing studies have mainly explained disparities in general practitioner (GP) resource allocation from single-factor or linear perspectives, with limited attention to the synergistic effects of multiple conditions and their underlying mechanisms.

To identify multiple pathways leading to stronger primary healthcare service capacity and to examine the associations between different configurations and the equity of GP resource allocation, as well as the mediating mechanism of primary healthcare service capacity.

Panel data of 31 provincial-level administrative regions in China from 2011 to 2024 were selected. Data were obtained from health and population statistical yearbooks and official public sources. Missing values were supplemented by linear interpolation, and variables were pre-processed via standardization, logarithmic transformation and other approaches. Taking the equity of general practitioner resource allocation as the explained variable, economic-social-policy conditions as antecedent conditions, and primary healthcare service capacity as the mediating variable, relevant control variables were also set. Fuzzy-set qualitative comparative analysis (fsQCA) was adopted to identify multiple configurations for achieving high-level primary healthcare service capacity. The configurational membership scores were quantified and incorporated into regression models to hierarchically test the direct effects of configurations on the equity of general practitioner resource allocation and the mediating transmission effect of primary healthcare service capacity.

Four equivalent pathways to high primary healthcare service capacity were identified: an economic-fiscal-social demand synergy-driven pathway, an economic-urbanization-population aging synergy pathway, a demand-policy support strengthening pathway, and an economic-urbanization-primary care supply synergy pathway. The overall consistency and coverage were 0.865 and 0.723, respectively. The economic-urbanization-primary care supply synergy pathway was significantly and positively associated with the equity of GP resource allocation (P<0.05). After primary healthcare service capacity was included in the regression models, it remained significantly and positively associated with GP resource allocation equity across all models (P<0.05). The direct associations of different configurations showed marked heterogeneity: the demand-policy support strengthening pathway had a significant positive association (P<0.05), whereas the economic-urbanization-primary care supply synergy pathway had a significant negative association (P<0.05).

The equity of GP resource allocation exhibits clear configurational heterogeneity, and primary healthcare service capacity may serve as an important pathway through which combinations of macro-level conditions affect equity. Differentiated resource allocation strategies should therefore be developed according to regional development conditions and population needs, while greater emphasis should be placed on strengthening primary healthcare service capacity.