Evaluating a multi-component, community-based program to improve adherence and retention in care among adolescents living with HIV in Zimbabwe: study protocol for a cluster randomized controlled trial

Background: World Health Organization (WHO) adolescent HIV-testing and treatment guidelines recommend community-based interventions to support antiretroviral therapy (ART) adherence and retention in care, while acknowledging that the evidence to support this recommendation is weak. This cluster randomized controlled trial aims to evaluate the effectiveness and cost-effectiveness of a psychosocial, community-based intervention on HIV-related and psychosocial outcomes. Methods/design: We are conducting the trial in two districts. Sixteen clinics were randomized to either enhanced ART-adherence support or standard of care. Eligible individuals (HIV-positive adolescents aged 13-19 years and eligible for ART) in both arms receive ART and adherence support provided by adult counselors and nursing staff. Adolescents in the intervention arm additionally attend a monthly support group, are allocated to a designated community adolescent treatment supporter, and followed up through a short message service (SMS) and calls plus home visits. The type and frequency of contact is determined by whether the adolescent is "stable" or in need of enhanced support. Stable adolescents receive a monthly home visit plus a weekly, individualized SMS. An additional home visit is conducted if participants miss a scheduled clinic appointment or support-group meeting. Participants in need of further, enhanced, support receive bi-weekly home visits, weekly phone calls and daily SMS. Caregivers of adolescents in the intervention arm attend a caregiver support group. Trial outcomes are assessed through a clinical, behavioral and psychological assessment conducted at baseline and after 48 and 96 weeks. The primary outcome is the proportion who have died or have virological failure (viral load >= 1000 copies/ml) at 96 weeks. Secondary outcomes include virological failure at 48 weeks, retention in care (proportion of missed visits) and psychosocial outcomes at both time points. Statistical analyses will be conducted and reported in line with CONSORT guidelines for cluster randomized trials, including a flowchart. Discussion: This study provides a unique opportunity to generate evidence of the impact of the on-going Zvandiri program, for adolescents living with HIV, on virological failure and psychosocial outcomes as delivered in a real-world setting. If found to reduce rates of treatment failure, this would strengthen support for further scale-up across Zimbabwe and likely the region more widely.