Intervention
Participants in the intervention arm received a digital, crowdsourced, multilevel intervention developed through a series of crowdsourcing open calls tailored for MSM (Profile of the digital, crowdsourced, multilevel intervention.The individual-level intervention included the digital intervention materials and HIV self-testing services delivered with digital tools. The digital intervention materials included 25 images and 4 videos, which were distributed by WeChat. After completing the 6-month follow-up survey, participants in the intervention arm could apply for the digital HIV self-testing services, including the free HIV blood self-test kits, use instructions, and counseling services, through WeChat. HIV self-testing counseling services were provided based on guidelines from the WHO, including pre-and posttest counseling [For the community-level intervention, we set up 8 peer-moderated WeChat discussion groups in the intervention arm. All participants in the intervention arm received an invitation to join a group and made their own decision on whether to join. Each WeChat group consisted of 1 team member, 1 CBO volunteer, and about 20 participants. The messages about HIV testing and safe sexual behavior came from authoritative facilities (eg, CDCs, CBOs, and hospitals) and were shared through WeChat groups and WeChat moments (a function on WeChat that allows people to share their life with friends) biweekly. In addition, members in the WeChat groups were encouraged to discuss HIV prevention.