What is?

The Evidence Map is a review methodology that allows the systematization and graphical representation of the evidence analyzed in review studies in an area or subarea in relation to the effect of the analyzed interventions on health outcomes.

In the Map, the selected studies are presented in a structure of interventions evaluated against measured results or outcomes, visually highlighting the gaps where there are few or no studies and where there is a concentration of them.

BIREME, taking into consideration the 3ie Evidence Gap Map model, adapted and developed a methodology for creating Evidence Maps linked to the information sources of the Virtual Health Library (VHL).

How to use?

The evidence map presents, in a matrix of interventions and outcomes, an overview and a graphic synthesis of the evidence on interventions of practices and/or therapeutic methods for specific health problems (outcomes).

The map is prepared in a process that involves a systematic search of documents in the main databases, study selection according to inclusion criteria, and subsequent characterization.

Is developed on an interactive online platform that allows users to identify existing evidence. In the matrix cells, the circles located at the intersections between the interventions and the outcomes represent the identified studies. The size of the circle represents the volume of studies. The color of the circles represents the confidence level (high, moderate, low, critically low) according to a methodological qualification of the studies included in the map. Review studies are evaluated using the AMSTAR 2 (Measurement Tool to Assess Systematic Reviews).

Hovering over a circle displays a list of the studies that the figure represents. The links for these studies lead to the full text (if open access is available) or to the corresponding record in a database of the Virtual Health Library (VHL). It is possible to filter the evidence by type, country foccus, effect of the intervention (positive, negative, etc), and population.

How to create?

The map is created by a process that involves a systematic search of documents in the main databases, study selection according to inclusion criteria, and subsequent characterization.

The follow step is creation and publication of evidence map to produce an interactive visualisation of evidence found, analyzed and categorized, in addition to linking with the bibliographic records and full texts (when available) of the studies.

And, based on the analysis of the review studies identified and analyzed, an executive report or scientific article should be organized in order to demonstrate the evidence gaps and redundancy (multiple studies of similar issues) related to specific area.

• Search
  The bibliographic search for scientific evidence will be carried out in electronic databases with the help of librarians and complemented by manual search and/or indication of specialists collaborating on the project.
• Selection
  In this stage of the project, the scientific evidence (scientific articles) identified in the bibliographic search will be evaluated according to previously defined criteria.
• Characterization / Categorizatio
  In this stage, data from the studies included in the previous stage will be extracted considering previously defined categories and reading the full texts of the selected studies.
• Interactive visualisation
  The creation and publication of evidence maps consists of graphically representing the evidence found, analyzed and categorized, in addition to linking with the bibliographic records and full texts (when available) of the evidence studies. Tableau Public is the tool being applied by BIREME to generate and publish an interactive visualization evidence map.
• Report (Gaps, Redundancy)
  Based on the analysis of the review studies identified and analyzed, an executive report or scientific article should be organized in order to demonstrate the evidence gaps and redundancy (multiple studies of similar issues) related to specific area, contributing to the establishment of national research agencies research priorities and among researchers.