BACKGROUND: Social network testing approaches (SNA) encourage individuals or ‘seeds’ to motivate sexual partners and/or those in their social networks who may benefit from HIV testing to test for HIV. To inform the World Health Organisation Guidelines Development Group, we conducted a systematic review to guide recommendations regarding SNA as an additional testing approach for all populations.
METHODS: We systematically searched five databases: Medline, Embase, Global Health, CINAHL and Web of Science, from Jan 2010 to July 2022. We included randomized controlled trials (RCT) and non-randomized studies (NRS) that compared SNA with non-SNA or that compared different types of SNA. We used random-effects meta-analysis to combine effect estimates of studies that shared similar interventions, control, and outcomes. Certainty was assessed using the GRADE approach.
RESULTS: From 18,956 records, we included 43 unique studies: 11 studies for the effectiveness of SNA vs. non-SNA, 10 studies for the effectiveness of different types of SNA, four studies for resource use of SNA vs. non-SNA, three studies for resource use of different types of SNA, and 23 studies for the acceptability of SNA. Based on one RCT and four NRS with low certainty evidence, SNA may increase uptake of HIV testing services compared to non-SNA (Pooled RR 1.67, 95%CI:1.35–2.05, I²=99%). Based on four NRS with moderate certainty evidence, the proportion of first-time testers was probably higher among partners or social contacts of seeds using SNA (compared to non-SNA) (Pooled RR 1.23, 95%CI:1.01–1.48, I²=97%). Based on eight NRS with low certainty evidence, the proportion of people who tested positive for HIV may be higher among partners or social contacts of seeds using SNA (compared to non-SNA) (Pooled RR 2.28, 95% CI: 1.18–4.39, I²=95%). High heterogeneity for these outcomes were mainly explained by population type and type of SNA.
CONCLUSIONS: SNA for HIV testing may be an effective, acceptable, and cost-effective approach to improve HIV testing in all populations. The type of SNA to implement should be based on the setting, epidemiology, client preferences and resources available. SNA should be further scaled up to strengthen global efforts to end HIV as a public health threat by 2030.