DESIGNING OPTIMAL WEB ACCESSIBILITY FOR OLDER ADULTS is an important issue that web designers should consider. According to the U.S. Bureau of the Census (1996), people over the age of 65 is the fastest growing group of the US population. We can safely assume that there will be an increase use of computer by the older adults.
Because of decreased working memory efficiency, decline in vision, reduction in motor coordination, and reduced attention spans, web designers should consider design elements that will facilitate this audience's Internet experience. Web design elements that can make web sites more accessible to older adults are navigation, color and contrast, font, page length, and distractions.

Studies show that older adults have difficulty finding information that they want when they have to follow more than three hyperlinks. The decline in performance arises because older adults tend to have trouble remembering their location within a site due to a decrease in spatial and working memory. Consider the following to design a web site with good navigation:

• Avoid a very deep hierarchy.

• Use clearly visible navigational aids to help them visualize the structure of the site.

• Provide clear and consistent navigation mechanisms —orientation information, navigation bars, a site map, and index.

• Explicitly state the site's content at the beginning of the site.

• Provide clear and large headings to help orient users. 

This is an example of a web page that doesn't have a hierarchical navigation structure. There is no heading to orient the users or navigational aid to help the users find their way around this site.

This is an example of a web page that demonstrates good navigation. The site content is presented at the beginning, and there is a clear navigation on the left to help the users get around the site.

As older adults aged they have difficulties with color and contrast differentiation. They have reduction in the transmission of blue light, have more trouble with sorting and matching colors, and make more errors in the short wavelength and blue-green regions than in the other color regions (Bernard). A diminished ability to distinguish between light and dark due to a reduction of light through the retina is another characteristic of aging (Bernard). When choosing color combinations, consider the following:

• Avoid bright, fluorescent, or vibrant colors.

• Avoid colors in the short wavelength and blue-green regions.

• Avoid using colors of similar lightness.

• Avoid using colored text on a colored background.

• Use dark types on light or off-white backgrounds.

• Choose colors from opposite sides of the color wheel.

Vision is the most common physiological change with aging. A diminished field of vision and development of short-sightedness or other visual disorders can impair visual acuity. Choosing the size and typeface of fonts is critical to the readability of text on computer screens.

• Avoid using several types of fonts mixed together or very narrow or decorative fonts.

• Don't use all caps.

• Use larger size for heading to distinguish between the body text and heading.

• Use bold only to emphasize a title or a key word.

• Use sans serif fonts.

Because older adults have difficulties in maintaining attention over long periods of time, they get distracted and disoriented by extraneous visual noise such as pop-up ads, background graphics, and multiple windows.

• Avoid using animations or blinking images.

• Textured background.

Molly Lam
SDSU Educational Technology