Evidence Map
What is it?
The Evidence Map is a review methodology that allows for the systematic and graphical representation of analyzed evidence from review studies in a specific area or subarea, evaluating the effect of interventions on health outcomes. This map displays selected studies in a structure that relates the evaluated interventions to the measured outcomes, visually highlighting gaps (where there are few or no studies) and concentrations of studies.
BIREME/PAHO/WHO adapted and developed a methodology to create Evidence Maps based on the 3ie Evidence Gap Map model, linking them to the Virtual Health Library (VHL) information sources.
How to use it?
The Evidence Map provides an overview and a graphical synthesis of evidence on therapeutic interventions for specific health problems, organized in a matrix of interventions and outcomes. Its development involves:
- Systematic search of documents in major databases.
- Selection of studies according to inclusion criteria.
- Characterization of the selected studies.
The map is available on an interactive online platform where users can identify existing evidence. In the matrix, circles at the intersections between interventions and outcomes represent identified studies. The circle size indicates the volume of studies, while the color indicates the confidence level (high, moderate, low, critically low) according to the methodological quality of the studies, using the AMSTAR 2 tool.
Hovering over a circle displays a list of studies with links to full texts (if available) or to records in the VHL. It is possible to filter the evidence by type, country focus, intervention effect (positive, negative, etc.), and population.
How to create?
The process of creating an Evidence Map involves several stages: Planning, systematic search, selection, data extraction, data categorization, interactive visualization, and reporting.
These steps ensure that the Evidence Map not only graphically represents the information but also serves as a useful tool for identifying areas that need more research and for avoiding duplication of studies.
For detailed steps, please refer to the instructions provided alongside.
