Designing charts for cognitive impairment

In this article, I will show you how displaying labels can lead to accessible, interactive charts for those who are cognitive impaired. Keep in mind that making content accessible benefits all users, not only those with disabilities. That is true for this case since all users will analyze the charts much more quickly when the series labels are enabled.

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Feel free to jump straight to the next section if you are familiar with cognitive impairment.

To begin, here is a brief summary : Cognitive impairment covers a vast range of cognitive conditions that affect skills such as: remembering, learning, concentrating, decision-making, etc. And as DataViz comprehension requires most of these skills ; it is crucial to consider cognitive impairment accessibility during the design and development process of building charts.

The addition of including explicit series labels is key to creating charts that are accessible for those who are cognitive impaired. The demo below displays the effects of different types of intermittent fasting on human cardiometabolic health, focusing on energy metabolism.

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Cardiometabolic diseases are a group of common but often preventable conditions, including heart attack, stroke, diabetes, insulin resistance, and non-alcoholic fatty liver disease (source ed.ad.uk).

Even though the legend is well displayed beneath the chart, it still requires some cognitive effort to scan the chart, the legend, then bounce back to the chart to recognize which series is correlated to a specific color and legend name. These cognitive barriers can be easily reduced by simply adding labels near each series, as displayed in the demo below:

All you have to do to display the labels near each series is to add the series-label module:

<script src="https://code.highcharts.com/modules/series-label.js"></script>

Thanks to the series-label module that displays the labels automatically on the chart, this demo reduces the amount of mental effort to process, understand, and gain insights from the chart.

Let me know your favorite tips to make your chart more accessible for those with cognitive impairment in the comment section below.