Design considerations for Macular degeneration

Question

So I was doing some research around the different kinds of conditions people face and what designers can do to ensure accessibility for them. I found some really good material at WebAIM.org.

This page about low vision talks about various conditions people face with limited vision. One such condition is Macular degeneration.

As per the site:

The macula is near the center of the retina, which is the area in the back of the eye. The aging process and the thinning of the tissues of the macula cause the most common form of macular degeneration,"dry" macular degeneration. The result is a gradual loss of vision. "Wet" macular degeneration occurs when abnormal blood vessels at the back of the eye begin to leak fluid or blood and blur central vision, often resulting in rapid loss of vision. In either case, the person's central area of sight is affected the most, making it difficult to see objects that the person is looking at directly. The images below are a simulation of the effect of macular degeneration. Text can appear broken and unclear.

From what I understand, everything a person focuses on, would be blocked as it's the very center of focus that's affected. If this is the case, what would be some measures a designer could take to ensure proper usability?

I tried looking around but could not find anything specific to this condition.

I'm actually researching specifically for data visualization, but in this case am open to generic answers as well.

Answer 1

Macular Degeneration prevents you from focusing on what is in front of you. I have seen how people with this condition work (I worked with someone with this condition) and how some software features help them and others hinder them. There are external software tools which can also help, e.g. a Fresnel lens over their monitor, software zoom feature, etc. Many people with this condition sit extremely close to their screens and zoom the screen as large as they can, and move their head around the screen, so that their peripheral vision can be utilised to view the details.

Features of your browser or the software you are using can also help, e.g. you can zoom a browser's view very high in modern browsers.

Creating a design where the page can adapt it's layout to something simpler and more linear helps too.

Things which are not helpful are complex page layouts because it can be harder to work out where you are when the screen is zoomed very high.

You can use this simulator to experience how someone with macular degeneration experiences the world: http://www.amd.org/what-is-macular-degeneration/experience-what-amd-looks-like/

So how does this impact on your data visualisations? You need to ensure the meaning encoded in the visualisation can be easily discerned by someone who can only see part of it.

Answer 2

Designing with WCAG 2.0 AA in mind will help with all kinds of vision issues, including color deficiencies (color blindness), color contrast (common in aging eyes), and magnification (zooming text).

Regarding data visualization, that's a huge topic. How do you make graphs (bar charts, scatter plots, etc) accessible to those with low or no vision? It's an area we've been researching for years and we're hoping to release some versions of our software that will aid in that area this year.

From a design perspective, for data visualizations, you can still apply WCAG. Have sufficient color contrast, don't distinguish between different series in a chart using color only (eg, use patterns), use SVG or some scalable graph so that magnification doesn't become pixelated, etc.