Behavioral Intervention for PrEP Service Utilization Among Chinese MSM: A HAPA and CEI Integrated Model

The intervention group will receive a 3-month technology-facilitated PrEP intervention and tailored messages will be developed using BCTs based on theoretical guidance. PrEP teleconsultations will be delivered by certified healthcare professionals, including infectious disease specialists, CDC-affiliated prevention officers, and MSM community leaders. Participants will be stratified into peer cohorts through algorithm-driven grouping based on demographic characteristics. Six participants will form a peer group, and the economic incentive amount will be based on the group-level PrEP initiation rates (verified by physician prescriptions). The economic incentive will decrease progressively based on the average completion rate within the group and will be divided into three tiers: 22 USD (completion rate of 80-100%), 11 USD (completion rate of 50-79%), and 0 USD (completion rate \<50%).

This group receives information pushes via a mini-program (3 messages per week) and two brief PrEP consultations; the first brief consultation is delivered jointly by community volunteers and a physician immediately after the baseline survey completion, based on a standardized consultation outline, and the second brief consultation is delivered jointly by community volunteers and a physician after the completion of the first monthly assessment (conducted within the mini-program), based on the standardized consultation outline and the results of that monthly assessment.