Both written and visual content should be accessible to people with disabilities. It has been estimated that 15% of the world’s population has a disability (United Nations, Marriott). Common disabilities include but are not limited to those that affect motor skills, vision, hearing, and cognitive functioning. For this reason, it is often necessary to provide content in multiple or alternate formats. While outlining full accessibility guidelines is beyond the scope of this document, here are some basic principles to keep in mind.
Use simple sans serif fonts, such as Arial or Calibri. Serif fonts, such as Times New Roman or Garamond, can be harder for people with cognitive disabilities or dyslexia to read.
Avoid fonts that are cursive, italicized, or otherwise hard to read.
Use bold for emphasis instead of italics or underlining.
Text should be left-aligned instead of justified.
Use plain language—avoid jargon and idioms.
Break up denser texts by utilizing white space. Keep paragraphs short and include space between paragraphs.
Use built-in styles and headings to create sections as this kind of formatting is easier to navigate for people who use screen reading devices.
Use font size 12 or larger.
Underline and embed hyperlinks. Avoid lengthy URLs.
Supply documents as plain text instead of PDFs or create accessible PDFs. Standard PDFs are not accessible to people who use screen readers.
Provide alternative text (alt-text) for all non-text elements. Alt-text is a concise written description of what is shown in the visual.
Ensure there is sufficient contrast between the text and background.
Include alt-text that is concise, non-repetitive, and informative.
Avoid text-as-image or embedded text within images. These will not be picked up by screen reading devices and cannot be scaled for readers who may increase the text size.
Ensure sufficient contrast, not only for people with low vision but also for printing in grayscale or black and white.
Choose colors that are accessible to people with colorblindness. Avoid rainbows. Avoid reds, especially when paired with greens.
Don’t rely on color alone. For example, consider using shapes or textured lines.
Include headers for each row and column.
Avoid empty rows or columns.
Avoid split or merged cells.
Provide alt-text that summarizes the table.
Use simple table structures.
Never use tables to control layout and do not nest tables.
Include captions or subtitles.
Consider providing a separate text transcript.
Be aware of photosensitivity and include a warning if a video includes any flashing or high-intensity effects or patterns.
The most common accessibility issues are missing alt-text, poor color contrast, and important information being difficult to find (CBM). Many programs, such as those in the Microsoft Office suite, have accessibility checking functions built into them. There are also online tools that can provide accessible color palettes, audit the accessibility of websites, and simulate color blindness so authors can check their own figures. See the Tools and Resources section for links.
CBM. (2018). Digital accessibility toolkit. https://www.cbm.org/fileadmin/user_upload/Publications/CBM-Digital-Accessibility-Toolkit.pdf
Katsnelson, A. (2021). Colour me better: fixing figures for colour blindness. Nature, 598, 224–225. https://doi.org/10.1038/d41586-021-02696-z
Marriott, K., Lee, B., Butler, M., Cutrell, E., Ellis, K., Goncu, C., Hearst, M., McCoy, K., & Szafir, D. A. (2021). Inclusive data visualization for people with disabilities: A call to action. Interactions, 28(3). https://interactions.acm.org/archive/view/may-june-2021/inclusive-data-visualization-for-people-with-disabilities
Rozaki, E., Kovačić, V., Charalampous, N., González, R. L., & Gabriels, W. (2020). Inclusive Communication Manual. Erasmus Student Network AISBL. https://siem-project.eu/documents/ESN_Inclusive_Communication_Manual.pdf
Schwabish, J., & Feng, A. (2021, September). Do no harm guide: Applying equity awareness in data visualization. Urban Institute. https://www.urban.org/research/publication/do-no-harm-guide-applying-equity-awareness-data-visualization
United Nations. (2022, March). Disability-Inclusive Communications Guidelines. https://www.un.org/sites/un2.un.org/files/un_disability-inclusive_communication_guidelines.pdf