Comparing the effectiveness of secondary distribution of HIV/syphilis dual self-testing to testing card referral in promoting HIV testing among gay, bisexual, and other men who have sex with men in Guangzhou, China: a quasi-experimental study

BACKGROUND: Social network approaches to testing allow individuals (indexes) to distribute tests to social networks (alters). This quasi-experimental study compared two social network-based testing strategies in promoting human immunodeficiency virus (HIV) testing among Chinese gay, bisexual, and other men who have sex with men (GBMSM). METHODS: GBMSM aged ≥18years were recruited from Guangzhou, China. From May to September 2019, indexes could distribute blood-based HIV/syphilis dual self-testing kits to people within their social network. Indexes recruited from October 2019 to January 2020 could send HIV testing cards to their social networks for free facility-based tests. Alters were encouraged to upload a photo verification of test results. Indexes and alters received incentives during both periods. RESULTS: There were 245 participants who were assessed for eligibility and 208/245 (84.9%) were eligible. 106 and 102 indexes were recruited in the secondary distribution and testing card arms respectively. 154/208 (74.0%) completed follow up at 1 month. 92 indexes in the secondary distribution arm self-reported distributions to 179 unique alters, and 62 in the testing card arm to 26 unique alters. An average of 1.95 (standard deviation [s.d.]=1.90) HIV/syphilis dual self-tests and 0.42 (s.d.=0.78) HIV testing cards were distributed, generating a risk difference of 1.53 (95% confidence interval [CI] 1.09, 1.96). Indexes self-identifying as gay (P =0.007) or having previously tested (P =0.02) distributed more tests. Secondary distribution cost less per alter tested (USD120 vs USD9408). CONCLUSIONS: Secondary distribution engaged more GBMSM to distribute tests and reached more GBMSM to test compared to referral cards, suggesting advantage in facilitating testing uptake among Chinese GBMSM.