Study design
RECRUITMENT, RECRUITMENT, SEXUALLY TRANSMITTED INFECTION
This is a multi-site, two-parallel, unmasked, individual-level RCTs conducted in seven Chinese provinces. Eligible participants met the following criteria: born biologically male, 18 years or older, reported anal sex with other men, not tested for HCV in the past year, reporting at least one of the following risk factors in the past year (condomless anal sex or diagnosed sexually transmitted infection (STI) or injection drug use), planning to live in China for the next month, and residing at a stable residence to receive a postal package securely. Participants were excluded if they were participating in similar clinical trials or other programmes involving HCV testing or were unwilling or unable to comply with all the study requirements. Eligible men were offered enrollment into one of two trials according to their HIV status. In trial 1, we enrolled men who had an HIV-negative result according to their laboratory test report in the past 3 months. In trial 2, we enrolled men who had an HIV-positive result confirmed by a test report. Recruitment took place from December 24, 2021, to January 30, 2022. Participants in each arm were followed for 4 weeks. The trial follow-up and data collection were completed on March 14, 2022. A pilot study was conducted to evaluate the feasibility of recruitment and to provide preliminary estimates of the effect sizes to partially inform the sample size and power calculations (Additional file We acquired permission from participants to assess their IP address before the study. We reported our findings according to the Consolidated Standards of Reporting Trials (CONSORT) guidelines (Additional file 