Effectiveness of nudge and motivational interview interventions to improve influenza vaccine uptake among healthcare workers in China: study protocol for a two-phase randomized trial

Seasonal influenza poses a significant public health challenge in China, yet vaccination uptake remains low even among healthcare workers. This study evaluates the effectiveness of multi-component interventions to improve influenza vaccination uptake, aiming to inform targeted public health strategies. A two-phase randomized controlled trial will be conducted in community hospitals across China targeting healthcare workers as participants. In phase 1, community hospitals will be randomized as units into one of three arms: standard nudge group, personalized nudge group, and control group. In phase 2, healthcare workers who remain unvaccinated after phase 1 will be individually randomized to either a motivational interview group or a control group. The primary outcome is influenza vaccination uptake, verified by official vaccination records. All data will be analyzed upon study completion. Nudge and motivational interview interventions are anticipated to significantly improve vaccination uptake among healthcare workers, and facilitate scale up of the effective interventions. By targeting healthcare workers, these interventions can also indirectly enhance vaccination coverage in the general population. ClinicalTrials.gov NCT07157163. Registered on September 4, 2025.