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AIDS and Behavior
Published in: AIDS and Behavior 8/2021

01-08-2021 | Human Immunodeficiency Virus | Original Paper

Assessing Potential Outcomes Mediation in HIV Interventions

Authors: Heather L. Smyth, Eileen V. Pitpitan, David P. MacKinnon, Robert E. Booth

Published in: AIDS and Behavior | Issue 8/2021

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Abstract

Knowledge of causal processes through mediation analysis can help improve the effectiveness and reduce costs of public health programs, like HIV prevention and treatment interventions. Advancements in mediation using the potential outcomes framework provide a method for estimating the causal effect of interventions on outcomes via a mediating variable. The purpose of this paper is to provide practical information about mediation and the potential outcomes framework that can enhance data analysis and causal inference for intervention studies. Causal mediation effects are defined and then estimated using data from an HIV intervention randomized trial among people who inject drugs (PWID) in Ukraine. Results from a potential outcomes mediation analysis show that the intervention had a total causal effect on incident HIV infection such that participants in the experimental group were 36% less likely to become infected during the 12-month study than those in the control arm, but that neither self-efficacy nor network communication mediated this effect. Because neither putative mediator was significant, measurement and confounding issues should be investigated to rule out these mediators. Other putative mediators, such as injection frequency, route of administration, or HIV knowledge can be considered. Future research is underway to examine additional, multiple mediators explaining efficacy of the current intervention and sensitivity to confounding effects.
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Metadata
Title
Assessing Potential Outcomes Mediation in HIV Interventions
Authors
Heather L. Smyth
Eileen V. Pitpitan
David P. MacKinnon
Robert E. Booth
Publication date
01-08-2021
Publisher
Springer US
Published in
AIDS and Behavior / Issue 8/2021
Print ISSN: 1090-7165
Electronic ISSN: 1573-3254
DOI
https://doi.org/10.1007/s10461-021-03207-x

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