Incentivizing primary care utilization in China: the impact of health insurance coverage on health-seeking behaviour

China's healthcare system faces significant challenges, notably the underutilization of primary healthcare resources and the inefficient distribution of healthcare services. In response, this article explores the effectiveness of the New Rural Cooperative Medical System (NRCMS) in improving healthcare accessibility and primary care utilization. Employing a multi-period difference-in-differences model and using data from the China Family Panel Studies spanning 2012-20, it aims to empirically examine how health insurance policy incentivizing primary care influences rural residents' health-seeking behaviour and enhances the efficiency of resource utilization. Results indicate that NRCMS significantly improves the probability of rural residents seeking healthcare services at primary healthcare centres (PHCs), especially for outpatient services. This effect can be attributed to the substantially higher outpatient reimbursement rates at PHCs compared to higher-level medical institutions. Conversely, the Urban Resident Basic Medical Insurance fails to increase urban residents' engagement with primary care, reinforcing the role of price sensitivity in healthcare choices among insured lower-income rural population. Furthermore, the study reveals a stronger preference for PHCs among younger, less-educated insured residents and highlights a synergistic effect between the availability of primary healthcare resources and insurance coverage on primary care utilization. These findings offer crucial implications for refining health insurance policies to improve healthcare service accessibility and efficiency.