I have a project in which users will take a test involving varying shapes and angles. The purpose of the test is to assess their cognitive abilities. Users will be taking this test on a tablet which is mounted on a table. The test usually doesn't last more than 20-30 minutes. This is taken in a clinical setting, so users don't actually pay for the app and there is no competitor (I.E. there is 0 motivation for marketing this application).

At the moment, the tests all have a relatively high contrast ratio in their user interface. The shapes are pretty colorful with a black background. In some parts of the test, the user needs to compare the differences between two shapes (and sometimes it's the difference between one or two pixels).

My feeling on the matter is that the high contrast ratio is harmful in some way, but I really haven't found anything to quantify that feeling. Users have had ample opportunity to complain about the interface, but have never complained about it. Nobody says their eyes hurt after the session and I don't think the test is getting inaccurate results due to UI. I don't want to change this interface just because I don't "feel" good about it, but I have been looking for research on this subject (without finding any yet).

I could change the interface if I found research supporting any of these:

  • A high contrast UI makes it harder for users to see the differences between angles on digital displays.
  • A high contrast UI impairs focus on a given 30 minute task
  • A high contrast UI is harder for certain portions of the population to see (such as color blind people)
  • Any other scientific fact which demonizes a high contrast UI.

On the flip side, if we find something supporting the high contrast UI, it would be helpful to know that as well so that I can defend the interface in the future.

Does anyone have a well-supported reason for me to change the interface or should I just leave it as high contrast?


1 Answer 1


People in Autistic spectrum often have issues with parsing high-contrasted visuals. This was researched as a Scotopic sensitivity syndrome: http://www.autism.com/understanding_irlens

On the contrast and readability correlation in common population: http://www.uxbooth.com/articles/4-tips-and-tricks-for-more-legible-content/

According to the Web Content Accessibility Guidelines 2.0 (WCAG20), text should have a minimum contrast ratio of 4.5:1

There is a link to a tool for determining the contrast between two given colors.

  • Thanks for the answer! The Scotopic sensitivity thing seems like it could have a lot of relevance. The text readability may be slightly less relevant since the test will mostly have unique shapes. Jun 25, 2015 at 22:45

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.