Introduction

Adverse sexual and reproductive health (SRH) outcomes, such as unplanned pregnancies and HIV infection, disproportionately affect adolescent girls and young women (AGYW; aged 15-24 years) in east Africa. Increasing uptake of preventive SRH services via innovative, youth-centred interventions is imperative to addressing disparities in SRH outcomes.

Methods and analysis

From 2018 to 2019, we used human-centred design to co-develop a theoretically driven HIV and pregnancy prevention intervention for AGYW at private drug shops called Accredited Drug Dispensing Outlets (ADDOs) in Tanzania. The result, Malkia Klabu (Queen Club), was a customer loyalty programme designed to strengthen ADDOs' role as SRH providers while encouraging uptake of critical SRH prevention products among AGYW. Malkia Klabu members had access to free contraceptives and oral HIV self-test (HIVST) kits and earned punches on a loyalty card for other shop purchases; punches were redeemable for small prizes. Our pilot among 40 shops showed that intervention ADDOs had higher AGYW patronage and distributed more HIVST kits and contraceptives to AGYW relative to business-as-usual (ie, client purchasing) comparison shops. We will conduct a cluster-randomised controlled trial (c-RCT) among 120-140 ADDOs in 40 health catchment areas in Shinyanga and Mwanza Regions (Lake Zone), Tanzania. ADDO shop recruitment includes a 1-month run-in with a tablet-based electronic inventory management system for tracking shop transactions, followed by enrolment, randomisation and a 24-month trial period. Our c-RCT evaluating the human-centred design-derived intervention will assess population impact on the primary outcomes of HIV diagnoses and antenatal care registrations, measured with routine health facility data. We will also assess secondary outcomes focusing on mechanisms of action, evaluate programme exposure and AGYW behaviour change in interviews with AGYW, and assess shop-level implementation strategies and fidelity.

Ethics and dissemination

Ethical approval was granted from both the University of California, San Francisco and the Tanzanian National Institute for Medical Research. Study progress and final outcomes will be posted annually to the National Clinical Trials website; study dissemination will occur at conferences, peer-reviewed manuscripts and local convenings of stakeholders.

Trial registration number

NCT05357144.

BACKGROUND: Uptake of mobile phone surveys (MPS) is increasing in many low- and middle-income countries, particularly within the context of data collection on non-communicable diseases (NCDs) behavioural risk factors. One barrier to collecting representative data through MPS is capturing data from older participants.Respondent driven sampling (RDS) consists of chain-referral strategies where existing study subjects recruit follow-up participants purposively based on predefined eligibility criteria. Adapting RDS strategies to MPS efforts could, theoretically, yield higher rates of participation for that age group. OBJECTIVE: To investigate factors that influence the perceived acceptability of a RDS recruitment method for MPS involving people over 45 years of age living in Colombia. METHODS: An MPS recruitment strategy deploying RDS techniques was piloted to increase participation of older populations. We conducted a qualitative study that drew from surveys with open and closed-ended items, semi-structured interviews for feedback, and focus group discussions to explore perceptions of the strategy and barriers to its application amongst MPS participants. RESULTS: The strategys success is affected by factors such as cultural adaptation, institutional credibility and public trust, data protection, and challenges with mobile phone technology. These factors are relevant to individuals willingness to facilitate RDS efforts targeting hard-to-reach people. Recruitment strategies are valuable in part because hard-to-reach populations are often most accessible through their contacts within their social network who can serve as trust liaisons and drive engagement. CONCLUSIONS: These findings may inform future studies where similar interventions are being considered to improve access to mobile phone-based data collection amongst hard-to-reach groups.