Common accessibility & usability problems in PowerPoint presentations:

1. Use captioned graphics that enhance the presentation.

Graphics, figures, logos, and flow-charts are not accessible for many people using assistive technologies. This does not mean do not use graphics at all, it only means that you document the images or you add notes about the image in the notes section. Use graphics to enhance the presentation and provide cognitive links for the audience.

2.Use the PowerPoint slides to organize your text.

The text is not available for screen reader users if the information is not structured within auto layouts provided by PowerPoint program. Insert text using the PowerPoint auto-layouts or add all text that you have using the text field ALSO in the notes field.

3.Use high contrast and effective contrast.

Poor contrast between background and text makes the information difficult to read on the screen. But no colors or specific contrast make it more difficult for listeners to pay attention. Use high contrast like light colors on dark or dark colors on light. Review points from the Lighthouse Effective Color Contrast

4. Use multimedia as appropriate.

Multimedia (i.e. streaming video) could present a real challenge for deaf people and for people with visual impairments.

5. Limit text on the screen for visual reasons.

Too much or small text can pose problems for those with print disabilities. When presenting to a group consider the size of the print versus the size of the room and whether someone farther than the second row could see the font. If possible, view your slides on the screen you'll be using for your presentation. Make sure they are readable from the back row seats. Text and graphics should be large enough to read, but not so large as to appear "loud." Use upper and lower case - not all caps. As a reference consider no font smaller than 24 point but some “experts” recommend no font smaller than 30 point.

6. Limit text on the screen for cognitive reasons.

Consider the 6X6 rule-- no more than 6 bullets and not more than 6 words on a line, but this might be too much. Most people do not remember more than 4 points at a time. Simplify and limit the number of words on each screen. Use key phrases and include only essential information. I read that Steve Jobs uses a picture or just a picture with a couple of words in extremely large font. It turns out that Steve wants the audience to listen to him tell the story, rather than read the slides. Then to make them accessible to someone who needs to view them later, you can add all that text on the notes page.

7. Use images to enhance comprehension

Lack of images can make it harder for the audience to maintain attention or retain the information. Use good quality images that reinforce and complement your message. Ensure that your images maintain their impact and resolution when projected on a larger screen.

8. Use text effectively.

Use contrasting colors for text and background. Dark text on a light background is best. Patterned backgrounds can reduce readability of text.
Use Arial, Trebuchet or Verdana Fonts. Use Bold to Highlight, do not use color alone for emphasis, italics are harder to read
Visit the page from the Lighthouse on making text legible

9. Reduce Cognitive Load

by following principles by Atkinson and Meyer
  • 1. Signaling - Write a clear headline that explains the main idea.
  • 2. Segmenting - Break up the sides into digestible bites. Do not put too much information on one screen. Use the slide sorter to get an idea of your overall presentation.
  • 3. Modality Principle - reduce visual load by moving text off screen and narrating instead. Move text to the notes section.
  • 4. Multimedia Principle - use visuals with your words instead of words alone People learn better with words AND pictures than words alone.
  • 5. Coherence Principle - Remove all information not related to the main idea

Adapted From: Failure is not an option