Evaluation

Using an evaluation tool like Bobby is, ideally, only one component of evaluating a site's accessibility.

Steps in Evaluation

The first step in ensuring accessibility is to make sure your coding is accurate (through validation) and works across multiple browsers and platforms. Then, you should evaluate usability-related elements, such as navigation, labeling and content, and specifics like button size and site layout. Finally, make sure the site is accessible through evaluation and user testing.

User Testing

It is best to include persons with disabilities when you test your site.That said, user testing is not always practical at each stage of the development process, and, if you are testing, it may be difficult to recruit persons with disabilities. As a compromise, you can evaluate the accessibility of your website yourself.

Evaluation Methods

There are three ways to evaluate a site for accessibility, in order of comprehensiveness: 1) perform simple tasks and view your site with revised browser settings, 2) use automated evaluation tools, and 3) test with assistive technology, such as screen readers, talking web browsers and text only browsers. These are all useful techniques, and depend on the time you have available, how comprehensive you choose to be, the availability of assistive technology and the size of your budget.

Perform Simple Tasks

Move through the website using only the keyboard. Use tab keys (shift-tab will move you backward), the enter button, navigation skips and accesskeys to navigate and operate the site.

Revised Browser Settings

Netscape Navigator 4.8 provides an informal method for testing accessibility by allowing you to turn off style sheets, javascript, images and adjusting colors to black and grey. (Current versions do not allow you to turn off style sheets so they are not as useful.) To set-up Netscape Navigator 4.8 so that you can evaluate your site:

1. Download Version 4.8 (http://wp.netscape.com/download/archive/ client_archive47x.html#4.8%20English)
2. Go to File Preferences.
3. Click on Appearance. Choose "Use my fonts, overriding page-specific fonts."
4. Go to Colors. Choose black for Text and grey for Background. Choose "Always use my colors, overriding page."
5. Go to Advanced. Turn OFF all of the following: Load Images, Enable Java, Use Java Plug-in, Enable JavaScript, and Enable style sheets.

This will allow you to see how well your site performs without scripts, style sheets or color. All the content and functionality of the finished version should remain.

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Automated Evaluation Tools

There are a number of free tools that you can use to evaluate websites. All are helpful, and each is worth using.

Bobby

(http://www.watchfire.com/products/desktop/bobby/)

Probably the best known online evaluation tool, Bobby will evaluate a site for W3C guidelines or Section 508 regulations. Bobby indicates when a code guideline has been violated and recommends manual checks for items it cannot verify. You are limited in the number of pages that can be checked at a time (which is a bother), although you can download an unlimited version of Bobby 5.0 for $299. Inforamation about Bobby is available on the Watchfire site. (http://www.watchfire.com/products/desktop/bobby/).

A-Prompt (http://aprompt.snow.utoronto.ca/)

A-(Accessibility) Prompt is a free, user-friendly evaluation and repair tool that runs on Windows 95, 98, ME, 2000 and XP computers. A-Prompt reviews html and text files for accessibility, identifies probable issues, and provides a template for their correction. It is very complete and particularly helpful for correcting tables and checking linearity.

Download A-Prompt (http://aprompt.snow.utoronto.ca/download.html), to evaluate it. After downloading the file, click on the SETUP application icon. Once installed, locate the A-Prompt folder (saved by default in "ProgramFiles"). Use the "A-Prompt File Selector" icon within that file to load files for review. A-Prompt was developed by the University of Toronto and University of Wisconsin using W3C Web Accessibility Guidelines 1.0.

The Wave 2.2 from Temple University (wave.webaim.org/index.jsp)

The Wave checks for W3C and Section 508 code violations and shows how a screen reader will navigate through a site. Note that it does not recognize tabindexes, however, so you will have to check those manually.

Vischeck (www.vischeck.com/vischeck/vischeckImage.php)

The Vischeck website checks readability of websites, or images for several conditions of colorblindness.

UsableNet (www.usablenet.com)

UsableNet offers the Macromedia Dreamweaver Accessibility Suite (www.usablenet.com/frontend/508as_entry.jsp) as a free extension that enables accessibility testing in Dreamweaver. UsableNet also sells a number of products and services for evaluating and correcting website accessibility.

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Validation Tools

It is important to validate the html and style sheet code in your website since incorrect code may not be recognized by adaptive technology.

HTML Checker

Available at W3C (validator.w3.org).

Style Sheet Checkers

Available for downloading from W3C (jigsaw.w3.org/css-validator) and for testing online at the Web Design Group (www.htmlhelp.com/tools/csscheck/).

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Screen Readers

Screen readers enable persons with disabilities to hear the content and easily navigate through accessible websites and documents.

JAWS

JAWS (Job Access With Speech) is a leading screen reader from Freedom Scientific (www.freedomscientific.com). Versions 4.0 and above can read PDF files. It is based on Microsoft Software Accessibility (MSAA) standards and runs on PCs (MS-DOS) only. See the Tools section for more information on JAWS.

Window-Eyes

Window-Eyes is a leading screen reader from GW Micro.It is based on Microsoft Software Accessibility (MSAA) standards and runs on PCs (MS-DOS) only. See the Tools section for more information on Window-Eyes.

Talking Web Browsers

Talking web browsers enable persons with disabilities to listen to and navigate Internet Explorer websites.

IBM Home Page Reader (HPR)

HPR is an inexpensive and usable talking web browser. You can download a 30 day demo of Home Page Reader (http://www-3.ibm.com/able/solution_offerings/hprtrial3.html). HPR has most of the functionality of JAWS or Window-Eyes and is useful for demonstrating how adaptive technology works. It is only available for PCs. See the Tools section for more information on HPR.

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Text-only Browsers

Text only browsers display website content as text.

Lynx

Lynx is the best known of the text only browsers. Lynx displays website content as text, along with "alt" tag content. It is a useful tool for checking website accessibility.

LIFT Text Transcoder

UsableNet has recently introduced an automated text rendering application called the LIFT Text Transcoder that interprets and modifies website content based on user preferences. See a demonstration of the LIFT Text Transcoder on the Usable Net Website (http://www.usablenet.com/frontend/demoform.jsp?prod=tt)

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