DISCUSSION
youth‐friendly
Through the REACH adherence support system, participants received frequent counselling and DLF and had high levels of engagement in optional support strategies. Three key findings emerged about how the support system worked. First, regardless of the strategies chosen, AGYW reported benefitting most through pathways aligned with the IMB model of behaviour change: information about HIV and PrEP products, motivation to continue product use, and skills and resources to build self‐efficacy to adhere. Second, for this approach to be successful, participants had to develop close relationships with counsellors, be able to engage frequently and easily with the support system to access additional help and resources, and gain trust in the products and counsellors. Third, although there was wide variation in the menu options selected within and across sites, similar support strategies were used for oral PrEP and the ring, and all sites had similar rates of high adherence.Observational studies have supported the use of the IMB model to characterize barriers and facilitators of PrEP and antiretroviral therapy use among men who have sex with men [The three foundational pillars of the REACH approach—strong interpersonal relationship, ongoing support and trust—emphasize the importance of providing youth‐friendly and developmentally appropriate adherence support [A substantial barrier to replicating the REACH adherence support system in programmatic settings is the provision of DLF, due to cost and logistical challenges. In the HPTN 082 study, which found no effect of DLF on PrEP adherence [In our quantitative analysis, no single combination of additional menu options worked best to support adherence, but the same options were preferred during the use of both products. These findings suggest that PrEP delivery programmes should offer a choice of adherence support methods, including counsellor‐ and peer‐based options, as well as in‐person and mHealth options, to suit individual preferences and circumstances. Evidence for improved adherence from other regions and health conditions similarly highlights the promise of multi‐modal interventions that include education, counselling, youth‐friendly services and mobile technology [This study has several limitations. REACH participants were highly motivated, committing to 18 months of product use, and are not representative of the general population of AGYW in SSA. However, participants’ baseline characteristics [