“The difference that makes a difference”: highlighting the role of variable contexts within an HIV Prevention Community Randomised Trial (HPTN 071/PopART) in 21 study communities in Zambia and South Africa

ABSTRACT

This paper explores contextual heterogeneity within a community randomised trial HPTN 071 (Population Effects of Antiretroviral Treatment to Reduce HIV Transmission) carried out in 21 study communities (12 Zambian, 9 South African). The trial evaluates the impact of a combination HIV prevention package (including household-based HIV counselling and testing and anti-retroviral treatment (ART) eligibility regardless of CD4-count) on HIV incidence. The selection, matching and randomisation of study communities relied on key epidemiological and demographic variables and community and stakeholder support. In 2013, following the selection of study communities, a “Broad Brush Survey” (BBS) approach was used to rapidly gather qualitative data on each study community, prior to the implementation of the trial intervention. First-year process indicator intervention data (2014–2015) were collected during the household-based intervention by community lay workers. Using an open/closed typology of urban communities (indicating more or less heterogeneity), this qualitative inquiry presents key features of 12 Zambian communities using a list of four meta-indicators (physical features, social organisation, networks and community narratives). These indicators are then compared with four intervention process indicators in a smaller set of four study communities. The process indicators selected for this analysis indicate response to the intervention (uptake) amongst adults. The BBS qualitative data are used to interpret patterns of similarity and variability in the process indicators across four communities. We found that meta-indicators of local context helped to interpret patterns of similarity and variability emerging across and within the four communities. Features especially significant for influencing heterogeneity in process indicators include proportion of middle-class residents, proximity to neighbouring communities and town centre, the scale of the informal economy, livelihood-linked mobility, presence of HIV stakeholders over time and commitment to community action. Future interdisciplinary analysis is needed to explore if these patterns of difference continue to hold up over the full intervention period and all intervention communities.

KEYWORDS:

• Context
• variability
• heterogeneity
• community randomised trial
• HIV intervention
• Zambia

Acknowledgements

We would like to especially acknowledge all the participants from the 21 communities, the HPTN 071 Social Science Team (aside from authors) who were part of this research, Nulda Beyers and the HPTN 071 and HPTN MRC Publications Working Groups. Sandra Wallman’s work inspired this analysis. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIAID, NIMH, NIDA, PEPFAR, 3ie or the Bill & Melinda Gates Foundation.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The research was funded by the International Initiative for Impact Evaluation (3ie) with support from the Bill and Melinda Gates Foundation and by the other sponsors of HPTN 071 – namely the National Institute of Allergy and Infectious Diseases (NIAID) under Cooperative Agreements [UM1-AI068619, UM1-AI068617 and UM1-AI068613], with funding from the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR). Additional funding is provided by NIAID, the National Institute on Drug Abuse (NIDA) and the National Institute of Mental Health (NIMH), all part of NIH.