Cluster randomised controlled trial of home cook intervention to reduce salt intake in China: a protocol study

INTRODUCTION: Salt intake in China is twice the upper limit recommended by the WHO, and nearly 80% of salt is added during cooking. This study will develop a package of salt reduction interventions targeting home cooks and evaluate its effectiveness and feasibility for scale-up. METHODS AND ANALYSIS: A cluster randomised controlled trial design is adopted in this study, which will be conducted in six provinces covering northern, central and southern China. For each province, 10 communities/villages (clusters) with 13 families (one cook and one adult family member) will be selected in each cluster for evaluation. In total, 780 home cooks and 780 adult family members will be recruited. The home cooks in the intervention group will be provided with the intervention package, including community-based standardised offline and online health education and salt intake monitoring. The duration of the intervention will be 1 year. The primary outcome is the difference between the intervention and control group in change in salt intake as measured by 24 hours urinary sodium from baseline to the end of the trial. The secondary outcome is the difference between the two groups in the change in salt-related knowledge, attitude and practice and blood pressure (BP). ETHICS AND DISSEMINATION: The study has been approved by The Queen Mary Research Ethics Committee (QMERC2018/13) and Institutional Review Board of the Chinese Center for Disease Control and Prevention (No. 201801). The study findings will be disseminated widely through conference presentations and peer-reviewed publications and the general media. TRIAL REGISTRATION NUMBER: ChiCTR1800016804.