Evaluation of population-based sodium reduction strategies in China: protocol for a study using a combined quantitative and qualitative approach

Sodium intake in China is among the highest in the world, particularly in rural areas. A government-led national sodium reduction program has been implemented but evaluations of its implementation and effectiveness remain limited. The study will use a combined qualitative and quantitative approach and a before-after design, to monitor and evaluate the implementation and effectiveness of the sodium reduction program in the rural areas of four provinces geographically distributed throughout China: Heilongjiang, Shanxi, Guizhou, and Guangdong. Baseline data collected in 2021–2023 will be compared to follow-up data collected in 2024–2025. Population surveys will quantify changes in community knowledge, behaviors, dietary patterns, and sodium intake. Food retail surveys will assess changes in the sodium content of packaged food products, while stakeholder interviews will assess the extent to which the program has been implemented as planned across government, industry, health, and community organizations. The study has received funding and ethics committee approvals though timelines and study processes were significantly delayed by COVID-19. Baseline surveys of 2790 community members have now been completed, food composition data for 20 240 products has been collected, and there have been 37 stakeholders interviewed to date. This project will provide a robust evaluation of progress with implementation of China's national sodium reduction program in rural areas of the country. It will quantify impact to date and provide insight into what has worked, as well as what has not, and inform future sodium reduction strategies.