Assessment of public information understanding using plain language and data visualization

Understanding is an essential quality in the presentation of information, mainly to promote democracy, transparency, and citizen participation in open government data (OGD). Data visualizations are common in open data portals and public services, but there is still a lack of consolidated practices for their publication and evaluations aimed at understanding users. Above all, add the Plain Language technique, which helps to make information more understandable for everyone and reduce barriers to the inclusion of a poorly literate public. This research evaluated the impact of the practices of this language gathered in a usage Guide for creating graphics understandable to the public in relation to other visualizations. The study was carried out with users of public health visualization in the context of the COVID-19 pandemic. The results showed that the use of the Guide improved understanding in tasks with fewer variables and data involved. An important insight for the development of dashboards and public portals with visualizations accessible to all. However, with challenges to be overcome mainly in the size and complexity of the various practices to be followed, making it difficult for users to fully use the Guide. Investing in researching a user support system can ensure higher quality graphics.