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Dragonfly
Winter 2002 -- Volume 33, Number 1 |
Drexie Malone is collaborating with the Pacific Northwest Regional Medical Library by investigating how well its new Web look is accessible to all.
Web page access for the disabled is a timely subject for almost any library, whether hospital, public, or academic. The number of Americans with disabilities who can benefit from access to the World Wide Web (WWW) is significant. Approximately 10% of the American population has vision, auditory, mobility, or cognitive disabilities that jeopardize their WWW access (1). Recent government regulations require federal Web sites to meet accessibility standards.
Many libraries have successfully responded to the increased demand for computer and Internet access for the majority of their users. People with disabilities, however, have seen their information access actually diminish. Features such as the graphical user interface (GUI), images, and animation have improved use of the Web for most people. At the same time, these innovations have made it harder for people who have disabilities. Text-based Web pages, which were originally the only format on the WWW, opened a whole world of information to people with vision problems. But adaptive technology devices used by the visually impaired - screen readers, for example - do not 'read' images; they read only text. In addition, screen readers do not interpret animation or tables and columns.
Web innovations can also be confusing or useless to those who have other kinds of disabilities. A person who is deaf will miss the presentation of a video clip that is not accompanied by closed-captioned text. Animation with sound and streaming video are also obstacles for people with auditory impairments. Reduced mobility (from an accident, repetitive stress injury, or permanent physical limitations) requires an alternative to the mouse to navigate Web pages. Such alternative technology includes keyboard navigation instead of a mouse, mouth sticks, head pointers, eyegaze-operated keyboards, and infrared devices.
People with learning disabilities may not understand all of the information presented on a busy, disorganized Web page. Unless the format is simplified and repeated, those with cognitive impairment will not benefit from the dense information presented on Web pages.
Regulations
Amendments to the Rehabilitation Act of 1973, made in 1998, took effect in June 2001 (2). The changes to Section 508 of this Act require electronic and information technology used by the federal government to be accessible to people with disabilities. Enforcement is to be implemented by suits against the government when users believe they have been denied equal access. Section 508 rules do not apply to private companies, but disability advocates hope the private sector will follow in opening up the WWW for disabled users.
Older legislation exists to support technology access for the disabled. The Americans With Disabilities Act of 1990 requires that appropriate aids and services be furnished to insure effective communication to individuals with disabilities (3,4). The Assistive Technology Act of 1998 requires that states receiving funding under the Act be subject to Section 508.
Solutions
The most prominent organization supporting accessibility is the World Wide Web Consortium (W3C), which promotes the Web Accessibility Initiative (WAI) on its Web site (http://www.w3.org/TR/WCAG10/) (5). The WAI guidelines cover 14 points, from text and language structure to making program elements like applets compatible with assistive technologies. Many Web page accessibility solutions use the W3C guidelines for direction. Guidelines can be extensive, or as simple as these, which were distilled by Dan Comden, consultant and manager of the Adaptive Technology Lab at the University of Washington (UW) (6):
If Web page designers do nothing more than follow these three basic guidelines, they will meet 90% of the needs of the disabled for Web page access. The Adaptive Technology Lab is associated with the DO-IT (Disabilities, Opportunities, Internetworking, and Technology) program at the UW, promoting "the use of electronic and information technology to maximize the independence, productivity, and participation of people with disabilities." (http://www.washington.edu/doit/)
Testing
In addition to implementing these guidelines, it is useful to test Web sites after the format has been implemented. One may test electronically by using a tool to check for Web page compatibility. "Bobby tested and approved" is the logo of an electronic tool, named Bobby, produced by the Center for Applied and Special Technology (CAST) (http://www.cast.org/bobby/ ) (7). The tool checks if Web pages meet the WAI guidelines. Pages must pass all priority 1, the lowest of 3 priorities, checkpoints for approval. One may submit the page Universal Resource Locator (URL) to the site and the results are presented online. Approved sites may display the Bobby-approved icon; the display is optional and not enforced.
Other sites provide Web access testing, including but not limited to, Pennsylvania's Initiative on Assistive Technology (PAIT), the TRACE center, and the Adaptive Technology Resource Centre (ATRC) (8). The WAVE 2.01 Web page accessibility check, produced by PAIT, also uses the WAI guidelines, checking for alternative text, reading order, structural tags, and keyboard shortcuts. The ATRC and the TRACE center have produced a Web accessibility verifier, called A-Prompt (9). This access tool will make repairs to correct HTML problems it detects, following WAI guidelines. The tool is downloaded to the user's computer. No test can perform a completely automatic check and cannot tell you if the page is truly accessible. The tool will check if images and links are labeled but cannot tell if the text is meaningful or useful. The Web architect must exercise judgment to conclude the page is accessible.
Finally, electronic testing of a Web site can be accomplished by reviewing the pages through a text-based browser, like Lynx, to experience how a person without vision would interpret the site. Such a browser is navigated with keyboard controls so the navigation design can be assessed. Another easy, inexpensive test is to shut off the graphics in the browser and see how the page looks to a screen-reader.
A second type of Web site analysis is usability testing. Web page usability can be defined simply as whether or not a page is easy to use. Usability refers to an "interface that is workable and intuitive from a user's point of view" (10). Qualitative information is collected when users are given a series of tasks to complete and their explanations are recorded. Jakob Nielsen, one of the best-known Web site usability experts, states that most Web site problems can be detected with as few as 5 to 15 subjects, generally 5 people per test (11). Another maxim is that 8 participants will identify 80% of the problems users might have with the system (12). Usability testing is a method whose time has come. The technique can be relatively brief, inexpensive, and effective. Testing replaces opinions with user-centered data.
The guiding principle of Web page accessibility for the disabled is that when changes are made to improve access for people with disabilities, all users benefit. With attention to clarity, consistency, and content of Web pages, information is more available to everyone.
Reference List
Dragonfly, Winter 2002
-- Volume 33, Number 1
(posted on PNRNews January 8, 2002)
This publication is funded in whole with Federal funds from the National Library of Medicine, National Institutes of Health, under Contract No. N01-LM-1-3516.
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