Study Participants and Setting
The study participants were enrolled using convenience sampling from June 15, 2021, to November 5, 2021. To ensure that we could recruit the required number of study participants from diverse backgrounds, potential participants were approached using social media (eg, Instagram). Local nongovernmental organizations that target MSM populations in Hong Kong also helped recruit potential participants based on their existing networks. Participants were eligible for inclusion in the trial if they self-identified as cis-male MSM aged ≥18 years with internet access and the ability to read and understand Chinese.