An ArcGIS Mapping Tool to Identify MPT Target Populations
Published: August 20, 2019
In sub-Saharan Africa, adolescent girls and young women are at the highest risk of acquiring HIV. However, as this is a heterogeneous population, the characteristics of these women can vary greatly. A one-size-fits-all approach simply will not work. In order for MPTs to have the greatest impact, approaches must be tailored to the populations where they are most likely to be successful.
In order to identify and characterize these priority sub-national areas and target populations with a high likelihood of successful and therefore impactful MPT uptake, the IMPT Secretariat, along with partners at Public Health Institute’s Survey Research Group (PHI SRG) and USAID, has developed an interactive MPT Target Population ArcGIS Mapping Tool. This tool allows users to explore mapped HIV prevalence and contraceptive method use data on the sub-national level for eleven PEPFAR countries in sub-Saharan Africa: Eswatini, Kenya, Lesotho, Malawi, Mozambique, Namibia, South Africa, Tanzania, Uganda, Zambia, and Zimbabwe.
The interactive mapping tool includes visual and tabular representations of data on HIV prevalence, total addressable market for contraception (TAMC), and contraceptive method use.
The aim of this activity was to identify the ‘hot spots’ where HIV prevalence and the total addressable market for contraception were highest. These are the areas where MPTs that provide contraception as well as protection from HIV infection could have the highest impact. In a recent update to the mapping tool, the contraceptive method mix was added to allow the user to understand other characteristics of women in these areas, including which contraceptive methods, if any, they are using, and whether this contraceptive method use varies by age.
The most recent, publicly available (as of July 2019) national datasets from the Demographic Health Surveys (DHS) and the AIDS Indicator Surveys (AIS) were used to calculate the TAMC, contraceptive method mix, and HIV prevalence for the eleven PEPFAR countries included on the map.
Weighted frequencies and percentages were calculated for all women, stratified by age categories, for HIV prevalence, TAMC, and contraceptive methods. The weight for women was applied in the analyses for the TAMC and contraceptive method mix, and the weight for HIV was applied in the analyses of HIV prevalence. Both weight variables were normalized by dividing by 1,000,000 prior to using in analyses. Cluster and stratum variables were included in all analyses, as appropriate for each country and each outcome of interest.
The weighted prevalence rates, the percentage of women who represent the TAMC and the percentage of women who are HIV positive within each region and 5-year age category were used to build an interactive map using ArcGIS that ranks ‘hot spots’ where both the TAMC and HIV prevalence are highest. Natural breaks were used to classify the HIV prevalence and TAMC data. The predominant contraceptive method used for women 15-24 years old within each region was mapped, as well as the proportion of contraceptive non-users. The map layers display data for women 15-24 years old, though data for other age groups and related variables can be viewed for each region using the map tools.
The mapping tool can be used to explore the HIV prevalence, TAMC proportion, and contraceptive data by region. Within the mapping tool, users can:
- Click on any region of the map to view region-specific data, including data stratified by age group.
- Swipe between map layers to explore possible associations, such as the most common contraceptive methods used in areas where HIV prevalence is highest.
- Modify and save high quality images of the map for use in reports or presentations.
- And more!
As MPTs are developed, it is critical to their success that each different product is targeted specifically at the population where it is most needed. But an equally significant consideration is whether a population in need is readily poised for product uptake. This is precisely why this mapping tool is so important. Looking at ‘hot spots’ as described above, users can see where women have a high need for HIV protection (high HIV prevalence), overlain with the women who have an interest in using modern contraceptives (total addressable market for contraception). With the contraceptive method use data, users can also pinpoint which methods are most commonly used (or least used) in an area–which can help to guide decisions about the formulation of new products and predict their likelihood of uptake.
This interactive ArcGIS mapping tool is intended for use by funders, product developers, and researchers, among others. With all of these different users in mind, we are continually working to improve this tool. It has been used so far to help inform study site selection for MPT end-user research, and to inform the market potential of specific MPTs in development. If you have any comments, suggestions, or simply want to tell us how you are or will be using this map, we’d love to hear from you. To learn more about the mapping tool, visit the linked documents on our website.
In this way, we hope to continue to maintain and expand upon this mapping tool, to provide an invaluable resource for the MPT field. Proposed next steps for this activity include:
- HIV incidence data
- STI prevalence and/or incidence data like HSV-2, chlamydia, and gonorrhea
- Expansion to other regions like the US and Asia
- End-user research
- A story mapping element
The development of this tool was also guided by an Expert Advisory Group including: Mike Chirenje (University of Zimbabwe), Thesla Palanee-Phillips (Wits Reproductive Health and HIV Institute), Chelsea Polis (Guttmacher Institute), Joseph Romano (NWJ Group), Meghan Reidy (Avenir Health), Elizabeth Russell (USAID Office of HIV/AIDS), and Michelle Weinberger (Avenir Health).