Strengthening China’s National Essential Public Health Services Package for hypertension and diabetes care: protocol for an interrupted time series study with mixed-methods process evaluation and health economic evaluation

Despite major primary health care (PHC) reforms in China with the 2009 launch of the National Essential Public Health Service Package, the country experiences many challenges in improving the management of non-communicable diseases in PHC facilities. "EMERALD" is a multifaceted implementation strategy to strengthen the management of hypertension and type-2 diabetes mellitus (T2DM) in PHC facilities. The study aims to: (1) examine the effectiveness of EMERALD in improving hypertension and T2DM management; (2) evaluate the implementation of the interventions; and (3) use the study findings to model the long-term health economic impact of the interventions.