HIV Prevention Knowledge Base
Structural Interventions: An Overview of Structural Approaches to HIV Prevention
I. Definition of the Prevention Area
A “structural approach” to HIV prevention is the process of selecting a set of interventions that address structural factors to reduce HIV risk at the individual and/or group level. Structural factors are elements outside of individual knowledge or awareness that have the potential to influence the vulnerability of individuals and groups to HIV infection. They can include social (e.g., stigma, gender inequality), legal-political (e.g., laws and regulations), cultural (e.g., religious beliefs), and economic (e.g., lack of livelihood opportunity) factors.
Structural factors fall into two conceptual categories:
- “Risk drivers,” factors that have been empirically shown to shape patterns of risk behavior in particular populations
- “Environmental mediators,” which increase people’s resilience to HIV (PDF, 1.23 KB) or hinder their ability to avoid HIV in a particular context (e.g., laws that criminalize and drive underground men who have sex with men , limiting their ability to seek HIV prevention services.)
II. Epidemiological Justification for the Prevention Area
There is a growing body of quantitative and qualitative evidence linking structural factors to HIV risk and its proximate determinants (e.g., multiple sexual partnering and lack of condom use). Given the complex and numerous pathways between structural factors and HIV transmission, however, few structural programs have been evaluated for their impact on HIV incidence.
Most of the emerging evidence centers on a few factors, including gender inequality, stigma and discrimination, economic empowerment and livelihood opportunities, education, and alcohol. For each of these factors, there is evidence on the impact of interventions that target them, although the relative importance of particular structural factors varies across settings.
One randomized controlled trial (RCT) that linked structural factors with HIV biomarkers found significantly lower levels of HIV and HSV-2 among Malawian schoolgirls who received monthly cash payments than among those who did not receive the payments. In Kenya, a study showed that reducing the cost of primary education by paying for school uniforms reduced dropout rates, teen marriage, and childbearing—all factors closely related to HIV risk. Other HIV prevention programs have addressed structural factors by changing norms around gender and violence against women, supporting micro-credit programs, and strengthening the legal rights of underserved populations. A recent Journal of the International AIDS Society (JIAS) supplement discusses the necessity of addressing these and other structural factors in future HIV investments. Service models need to be adapted to the economic and social environments of clients, and HIV programming incorporated into wider gender and development efforts.
III. Core Programmatic Components
There is now widespread agreement that structural approaches are a critical part of a “combination HIV prevention” strategy. In addition to the positive outcomes structural interventions can achieve on their own, they are important to the success of biomedical and behavioral interventions. For example, voluntary medical male circumcision provision programs may not realize their potential impact without including activities that address structural factors, such as socio-cultural norms that influence men and women’s preferences around circumcision (PDF, 1.18 MB) and mobility-constraining poverty that may limit access of certain populations to services.
There is no “one size fits all” structural approach that is appropriate for all epidemics, settings, or target populations. A defining component of a structural approach to HIV prevention is choosing a set of interventions according to evidence- informed analysis of the particular characteristics of the target population, the context, and of the risk drivers and environmental mediators of HIV in that specific setting. In a setting where, for example, migratory labor is common and laborers are found to have especially high levels of HIV, a structural approach could include workplace HIV prevention (PDF, 444 KB) interventions for migrant laborers or an intervention to create alternative sources of economic opportunity. In an epidemic where HIV is transmitted primarily through sex work, a priority intervention could be engagement of local authorities to enforce condom use in brothels.
Although there is no single structural approach appropriate for all settings, there are a number of key considerations and features characteristic of good structural programming. These should be addressed in the development and implementation of structural approaches in any setting:
- clear articulation of the causal pathway between the structural factor and HIV risk and of where along this pathway the intervention aims to have impact
- understanding of the intervention’s possible unintended effects
- definition of the macro (national/regional), meso (community), and/or micro (individual/family) level at which the intervention expects to have influence
- attention to the needs of marginalized and/or hard-to-reach groups.
These considerations are delineated in the AIDSTAR-One Structural Resource Tool (forthcoming).
IV. Current Status of Implementation Experience
Structural interventions are not new to public health prevention strategies. Well known and successful examples include increasing taxes to reduce or prevent smoking and national programs to put fluoride into drinking water to prevent tooth decay. In the HIV arena, however, the importance of structural interventions has only recently garnered significant attention. There is limited consensus around key concepts, definitions, what works, and the causal pathways through which successful programs create impact. This is in part due to gaps in the evidence base, many of which result from the technical challenges of measuring the impact of structural programming. The position paper series developed by AIDSTAR-One and STRIVE makes progress on some of these issues. It provides definitions for key structural HIV prevention concepts, analysis of the current evidence base and gaps, frameworks for approaching structural prevention, and lessons from field-based implementation experience.
Measuring the effectiveness of structural intervention programs can be difficult for several reasons:
- there is no direct, one-to-one relationship between structural interventions and HIV incidence
- structural interventions are often not amenable to randomization
- causal pathways from intervention to end point outcomes are usually indirect and complex
- there has been limited funding to study these questions at a scale proportionate with funding for research on biomedical and behavioral interventions.
Existing evaluations of the effect of structural interventions on HIV and proximal behavioral outcomes use multiple, diverse methodologies to allow triangulation of data. Methodologies include RCTs (PDF, 104 KB), quasi-experimental studies, and qualitative studies (PDF, 377 KB). Retrospective studies of broad national responses to the epidemic have combined sources and methods typically used in public health (e.g., HIV prevalence and incidence modeling, behavioral and demographic health survey data, interview and focus group data, and condom shipment data), with some not commonly used (PDF, 78 KB) (i.e., newspaper reports of behavior change). Limitation to conventional methods, such as RCTs, and basis on independent samples may undercut the development of new and effective HIV prevention approaches. Researchers have articulated the need for further engagement with social science methods and the use of combinations of data (PDF, 835 KB) from different types of evaluations, as well as careful inclusion of less rigorous sources to continue to make progress in generating the evidence base.
Updated: August 2013