An evaluation of accessibility of Covid-19 statistical charts of governments and health organisations for people with low vision

Abstract

During the Covid-19 pandemic, people rely on the Internet in order to obtain information that can help them understand the coronavirus crisis. This situation has exposed the need to ensure that everyone has access to essential information on equal terms. During this situation, statistical charts have been used to display data related to the pandemic, and have had an important role in conveying, clarifying and simplifying information provided by governments and health organisations. Scientific literature and the guidelines published by organizations have focused on proposing solutions to make charts accessible for blind people or people with very little visual rest. However, the same efforts are not made towards people with low vision, despite their higher prevalence in the population of users with visual impairment. This paper reviews the accessibility of the statistical charts about the Covid-19 crisis for people with low vision that were published by the Brazilian, British, Russian, Spanish, European Union, and the United States´ governments and also by the World Health Organization and Johns Hopkins University, relating to the countries most severely affected by the pandemic. The review is based on specific heuristic indicators, with a mixed quantitative and qualitative approach. Overall, the reviewed charts offer a reasonable level of accessibility, although there are some relevant problems affecting many of the low vision profiles that remain to be solved. The main problems identified are: poor text alternatives in both, raster images and SVG charts; the incompatibility with a keyboard interface; insufficient non-text contrast against adjacent colours (in chart elements such as bars, lines or areas), no customization options; and the lack of an optimized print version for users for whom reading on screen is challenging.