Observer in usability testing gets actual insight of the users while watching them using a product. But what about the users using adaptive technology? like blind web users, how blind users work with web sites? While surfing net, I found a very good case study where 16 blind users were observed while using screen readers to do some tasks on different web sites. Here I am briefing the main points of the same.

It’s a 10 years old case study, but still relevant and good to understand how blind users work with web site

Screen reader user scan with their ears

Most blind users are just as impatient as most sighted users. They want to get the information they need as quickly as possible. They do not listen to every word on the page – just as sighted users do not read every word. They “scan with their ears,” listening to just enough to decide whether to listen further.

Many set the voice to speak at an amazingly rapid rate. They listen to the first few words of a link or line of text. If it does not seem relevant, they move quickly to the next link. Blind users also object to listening to descriptions of elements, such as decorative bullets that add no meaning to the page, and that make them wait through three words to get to the real meaning.

Some Guidelines

• Write for the web. Write in short, clear, straightforward sentences. Write links that start with keywords.
• Use empty ALT text, ALT=”” or use a space as ALT-text, ALT=” ” for decorative elements on a page so that users do not have to listen to “decorative bullet image” or “decorative line.” Using empty ALT text for decorative elements complies with 508 guidelines. When links are bulleted, there is no need to identify the bullet, just the link name.

Extra cognitive load on blind user

Screen-reader users have already quite a mental load to understand the browser, the screen reader, and the web site. Most screen-reader users do not use the mouse. They completely depend on keyboard commands.

Vision-impaired users have to split their cognitive energy three ways – browsers, screen reader and web site

Some Guidelines

• It need to be taken care by the developer of screen-reader to make the command memorable and intuitive.
• Designers and developers of websites should make the structure clear and obvious to decrease the cognitive load of not only blind users. It helps the sighted users as well.

Content need to be screen readers friendly

Screen reader software does an amazing job but still we need to take care of small things to make the content clear and obvious for the blind users. here are a few guidelines that need to be taken care.

Some Guidelines

• Provide a link “Skip to main content” many users want to skip the navigation. Off course it doesn’t make sense to listening to the global navigation at the top of every page before accessing the main content.
• Do not make up unusual names for products, services, or elements of a Web site. Do not combine two or more words into one name. Like homepage should be written with space “Home Page”
• To make screen readers read an acronym or abbreviation as letters rather than attempting to read it as a word, use the acronym and abbr tags

Link “Skip Navigation” is not intuitive for the users

Navigation is a web jargon, which is understand by software professional and highly sophisticated computer users. Text which make more sense for the user is “Skip to main content” It is much more meaningful for the user.

Blind users use link list box

Web sites are made up of navigation pages and destination pages. Pages that are primarily used for navigation, sighted users often scan the page, focusing on the blue underline. Blind users are no different. They move the same way.

Screen readers assist them by allowing users to choose to listen only to links. Both JAWS and Window-Eyes users can do this by either tabbing from link to link or by calling up a Link List, a separate window that lists all the links on the page.

Make links descriptive

By using the link list users move quickly through the list and blind users use this regularly. They scanned the link list with their ears – even through the link list. They get frustrated, if the link start with same words. That’s why links like “Click here”, “more” and other meaningless links just do not work.

Some Guidelines

• Start links with relevant keywords
• Try not to have many links that start with the same word or phrase.

Some users are poor spellers, which make searching difficult

Some vision-impaired users spell poorly, which make successful searching difficult. Use search engine that provides help with spelling.

Screen reader users jump from heading to heading

Even most sighted users don’t read. They scan the content pages. Most screen reader users also want just the section that has the information that they need. JAWS allows them to skim through a document as sighted users do, moving from heading to heading by pressing H or using Insert-F6 to get a Headings List (just like a Links List).

Some guidelines

• Encourage authors to use many headings in their content and to be sure that those headings are clear, meaningful, and parallel.
• Be sure that the headings are coded properly in HTML, for example, as

  ,

  etc. JAWS looks for the heading tag.

• Put the keyword at the beginning of the heading. If many headings are about the same thing, differentiate them in meaningful ways.

Conclusion

After understanding how blind users use the web site. Usability and accessibility go hand in hand, there is relationship between accessibility and usability. There are already guidelines that helps to make website accessible but by just following the guidelines. It doesn’t sure that a website is usable for the blind users. Such research based guidelines help a lot. I have brief here some important point. To get more insights read this case study, it really worth your time.