Data and Accessibility

While data visualisation helps many people understand data, it’s very important to ensure that everyone, including those with disabilities, can access and benefit from it. This is where digital accessibility comes into play.

But what does this actually mean? Let’s look into a condition called colour blindness.

Colour blindness is a condition that affect how people see colours, making it difficult to see certain colours. This happens because our eyes have certain cells called cones that help us see colours, but in people with colour blindness, some of these cones do not work very well. Colour blindness is usually a condition we are born with, and it can run in families. For example, if one of our parents have it, we are likely to have it as well.

There are different types of colour blindness that affect how we can see different colours. The most common type makes it hard see the difference between red and green. Another type affects seeing blue and yellow. Being colour blind does not mean we see the world in black and white, but some colours may look the same. See the example on Figure 9, where we have a basket with green and red apples, lemons, and oranges. Now have a look at the colour blindness simulation done and how different types of colour blindness actually see. Have a look carefully and try to identify the different fruits.

Figure 9 – Image of a basket containing green and red apples, lemons and oranges, and the simulation of how Red- Colour blindness, Green- Colour blindness and Blue- Colour blindness would see this same image.

This same principle can be applied when we are building data visualisations. Imagine we want to build a column chart showing our grades for Mathematics, English and Science along the year. The original visual assigns the colours: green for English, yellow for Mathematics and red for Science.

Check out Figure 10 to see how this picture looks to someone who is colour blind. It’s pretty tough to tell things apart, right? It wouldn’t be fair to use this picture to explain what’s going on. This is why it’s super important to think about making our digital content accessible for everyone.

Column chart showing grades for English, Mathematics, and Science throughout the year. Alice’s English grades were 75, 80, and 85; her Math grades were 90, 88, and 92; her Science grades were 85, 82, and 88. Includes simulations showing how the chart looks under Red-Color Blindness, Green-Color Blindness, and Blue-Color Blindness. — Figure 10 – Grades for English Mathematics and Sciences along the year displayed on a column chart and a colour blindness simulation for Red-Colour Blindness, Green-Colour Blindness and Blue-Colour Blindness.

So, remember, when designing data visualisations, we need to consider everyone who might use them, including those with disabilities. We’ve discussed colour blindness, but there are other disabilities to keep in mind as well. For instance, some individuals have low vision or may be completely blind, relying on screen readers to understand the data. Others might have cognitive disabilities (like dyslexia), making it challenging to process complex visuals or large amounts of information at once.

By considering these diverse needs, we can create data visualisations that are clear and understandable for everyone. So, whether you’re working on a school project or creating content to share online, remember to make your data visualisations accessible—because everyone deserves to be included!

There are numerous resources available to support your learning journey. In the next chapter, I will provide a list of some valuable ones. Click here to check it out!

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