Chap11-Access-n-Users
Contents
Web Accessibility & Users – Chapter 11
Quotes:
"New information and communications technologies can improve the quality of life for people with disabilities, but only if such technologies are designed from the beginning so that everyone can use them.” – Bill Clinton
“People sometimes ask me, ‘What about accessibility? Isn’t that part of usability?” – Steve Krug
Accessibility Overview
What do we mean by accessibility
In previous chapters we have discussed Universal Design and general best practices for design. In this chapter we will narrow our focus to issues particular to disability and accessibility. We will look first at what we mean by “Web accessibility,” then review statistics on disability in the U.S.; discuss the particular access issues for each disability area; and, finally, discuss demographic trends in the U.S. and elsewhere related to aging and consider how this informs our discussion of Universal Design.
Web Accessibility vs. Usability
Earlier, [I think – check on this], we discussed the differences and similarities between the concept of Web accessibility and usability. Steve Krug asks the question directly in the second quote above, implying that accessibility is simply a part of usability.
What do you think? Is accessibility a part of usability? Let’s look at the definitions of both terms before answering.
Jacob Nielson defines usability as a “quality attribute that assesses how easy user interfaces are to use.” (Nielson - <a href="http://www.nngroup.com/articles/usability-101-introduction-to-usability/">http://www.nngroup.com/articles/usability-101-introduction-to-usability/</a>)
The ISO definition, mentioned in chapter 1, is "the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency, and satisfaction in a specified context of use."
Accessibility, on the other hand, is the design of products, interfaces and environments so that it can be used effectively by persons with disabilities. Specifically, it is about meeting the needs of people with disabilities. If Web accessibility is primarily about making sites usable by persons with disabilities, we are therefore talking about a special population. This distinguishes it from usability, does it not? The answer is yes and no. Yes – the population being addressed is the key difference between accessibility and usability. However, I would argue that accessibility is simply usability for persons with disabilities, it’s usability for a population we do not usually consider in our usability rubric. Otherwise, both are about designing websites so that the user interface can be used effectively with a minimal of frustration and effort by users. Coming back to our key theme – Universal Design is the broadening of usability to a wider audience.
Therefore we need to understand the needs of our wider audience. This is what we will do for the rest of the chapter: focus on audiences with “special needs,” audiences classified or considered persons with disabilities or impairment. I would caution you to remember that almost any accessibility consideration we discuss also has benefits for other users and other situations.
Disability Statistics
According to a 2010 Census survey, about 56.7 million or about 1 in 5 individuals (18.7 % of the non-institutionalized population) in the U.S. have a disability. <a href="#_ftn1" name="_ftnref1" title="" id="_ftnref1"> </a> Approximately 38.3 million (12.6% of the population) have a severe disability.
[Sidebar – problems with disability statistics]
One of the things that becomes noticeable (and frustrating) when referencing statistics on disability (and statistics in general) is the variation found between different studies. For example, the 2011 National Health Interview Survey measures the prevalence of vision disability at 21.2 million or 9.2%, or the non-institutionalized U.S. population, significantly higher than the Census estimate – 8.1 million - used below. Why the difference? How disability is defined, the way questions are asked, sampling methods and sizes and other factors can affect statistical outcomes.
Disability is not a binary (yes or no) determination, in contrast to measurements such as age or height and weight. If we know someone’s birth date, we can determine their age. Disability, on the other hand, is a continuum. Where on the scale of functioning we decide to demarcate disability will determine how many people are designated as having a disability.
The key different between the two studies compared here seems to be the definition of vision impairment. In the Census study, difficulty seeing was defined as
“experiencing blindness or having difficulty seeing words and letters in ordinary newsprint, even when wearing glasses or contact lenses”; in the NHIS, vision impairment was defined as “any trouble seeing, even when wearing glasses or contact lenses.” The NHIS parameters for vision impairment are clearly broader.
Many people with “any trouble seeing” may be able to see words and letters in ordinary newsprint without difficulty. The definitions of other disabilities in the Census study are all rather narrow. Therefore, the number of individuals with vision, hearing and other disabilities in the Census study is lower than in a number of other studies covering the same area.
[end sidebar]
Domains of Disability
The following chart provides the breakdown of disability across four categories: vision, motor (or mobility), cognitive/intellectual, and hearing (or auditory). Populations with limited or reduced functioning in these areas are the ones most likely to face obstacles with Web access.
Disability Category |
Number of Individuals |
Percentage of Population |
Vision<a href="#_ftn2" name="_ftnref2" title="" id="_ftnref2"> </a> |
8.1 million |
3.3% |
Physical/Mobility<a href="#_ftn3" name="_ftnref3" title="" id="_ftnref3"> </a> |
37.4 million |
16.2% |
Mental or Cognitive Disability<a href="#_ftn4" name="_ftnref4" title="" id="_ftnref4"> </a> |
10.6 million |
4.4% |
Hearing Disabilities<a href="#_ftn5" name="_ftnref5" title="" id="_ftnref5"> </a> |
7.6 million |
3.1% |
Let us look at each of these functional areas in more depth.
Vision
Vision impairments include blindness – legally defined as visual acuity of 20/200 or less after correction in the better eye or a visual field or no greater than 20 degrees<a href="#_ftn6" name="_ftnref6" title="" id="_ftnref6"> </a> - low vision or color blindness. Low vision, as defined by the Census 2010 survey is “having difficulty seeing words and letters in ordinary newsprint, even when wearing glasses or contact lenses” (pg. 8 Census 2000). Note that this definition of low vision is rather narrow – for example, color blindness would not be included under the Census survey’s definition of low vision. In addition, reading from paper is easier than reading from a computer display. Individuals who may able to read a newspaper without difficulty may find reading from an LCD more problematic. Thus, the number of individuals with vision disabilities or at least vision problems are probably underrepresented by the Census survey and hence at least partly explains the discrepancy with other studies (see side bar).
Hearing
Hearing impairments include deafness or difficulty hearing. Difficulty hearing is defined as “difficulty hearing a normal conversation, even when wearing a hearing aid” (pg. 8. Census 2010).
Cognitive/Intellectual
A cognitive/intellectual disability can range from perceptual/cognitive issues such as dyslexia to ADHD to memory loss to dementia.
Physical/Mobility
This can include: difficulty grasping, lifting or moving objects; difficulty walking, standing or climbing stairs; or problems with fine motor movement due to conditions such as ataxia or spasticity.
Accessibility Issues by Disability
Vision
Because the Web is primarily a visual interface, individuals with low vision or blindness are, perhaps, the demographic most often facing significant barriers accessing the Web and most often talked about when discussing Web accessibility. (However, we should not make the mistake of focusing only on screenreader users). [Mention - sidebar of initial Web].
Web Designers unfamiliar with Assistive Technology often ask if they need to provide audio output of the information on their website for blind or low vision users. The answer is a resounding “no.” Screenreader technology such as JAWS (Windows) or VoiceOver (Mac) allow voice output (the “reading” of screen text with synthesized speech) for individuals who cannot see or read the text or other objects on the screen.
Individuals with low vision may be able to read the screen through enlargement of the screen with products such as ZoomText or Magic. For some individuals, increasing the font size and/or selecting a high-contrast visual scheme through the Windows or Mac control panel is sufficient to allow effective reading and access to information displayed on a computer screen, whether a web page or the desktop of the computer.
[Highlight box]
<a href="http://www.w3.org/WAI/intro/people-use-web/stories#accountant">Read an online profile of a person with blindness</a> at the Web Access Initiative (WAI) website.
(Note: the site opens with the section More about Ms. Laitinen closed by default. Be sure to open us this section. Similarly the section Text alternatives for non-text content (Perceivable) under Sections related to Ms. Laitinen.)
[end: highlight box]
What Can Be Read by a Screenreader? The Importance of Alternative Text.
Although screen enlargement software can enlarge both text and images, and screenreader technology can read all text, only images that that have been marked up with alternative text (“alt attribute” in HTML-speak). Alternative text is a short description of the image or the information conveyed by the image. For example, if a web page contains an icon of printer as a control to print the page, the alt text should say “print page” and not “printer.” (@@@will be discussed further in ….???).
[sidebar: Google is deaf and blind billionaire]
Alternative text benefits not only blind and low vision users but also individuals with cognitive and intellectual disabilities who may use screenreader technology as well. In addition, alternative text aids search engine optimization (SEO) [@@@ see Google sidebar]. Therefore, ensuring that all the non-text elements on your web pages are labeled with alternative text is the most important and easiest action you can take to make your sites accessible. Alternatively, a page filled with images without alternative text will surely make your site inaccessible to both screenreader users and search engines. As a result your site will be less “findable” with Google, Yahoo, and other search tools.
[List other things you should do that we will cover in other parts of the book]
Hearing
As mentioned in the sidebar, the Web, at its inception, consisted only of text (and text-based hyperlinks). Not only was the image-free environment a benefit for individuals using screenreaders, the lack of audio benefited individuals with deafness or hearing loss.<a href="#_ftn7" name="_ftnref7" title="" id="_ftnref7"> </a> Similar to the obstacles faced by individuals with vision impairments with the rise of images, the proliferation of audio and multimedia on the Web has increased the likelihood that Deaf and Hard of Hearing individuals will encounter content that they cannot access.
[@@@ find out when audio and multimedia first appears on the Web]
For those with deafness or hearing loss, access to audio is provided through transcripts (for content which is exclusively audio) and captioning for multimedia (the display of text synchronized with the audio track). Unlike alternative text for images, providing transcripts and captioning is a challenging and time-consuming undertaking which usually requires the use of a 3rd-party transcription/captioning service or an in-house individual or team dedicated to its production.
[@@@ List other things you should do that we will cover in other parts of the book]
[@@@ Other benefits of captioning]
[highlight box:]
<a href="http://www.w3.org/WAI/intro/people-use-web/stories#onlinestudent">Read a profile of an individual with a hearing disability and adaptations required for access to the Web </a>.
(Also read the section More about Ms. Olsen)
[end: highlight box]
Cognitive/Intellectual
Individuals with cognitive/intellectual issues benefit from many of the same design features or Assistive Technology mentioned for individuals with vision impairment, including screen-enlargement, voice output and high contrast color schemes. The consistent placement of navigation throughout a site and the implementation of best design practices, such as proper use of whitespace, the alignment and grouping of content, and proper typography, also benefits both these groups (and all users for that matter). As mentioned above, the use of images and graphics to convey or supplement information is also beneficial to this audience.
[List other things you should do that we will cover in other parts of the book]
[highlight box:]
<a href="http://www.w3.org/WAI/intro/people-use-web/stories#classroomstudent">Read a profile of an individual with a cognitive disability and their use of Assistive Technology</a>.
(Also read the section More about Ms. Olsen)
[end: highlight box]
Physical/Mobility
Individuals with physical or mobility disabilities affecting their upper extremities (i.e. arms and hands) face issues of web and computer access, more so than for individuals with lower extremity issues. The reasons are obvious – we use our arms and hands to control the keyboard and mouse, and increasingly, a tablet or touch screen (and more recently, for gestures to control the user interface). Unlike the three disability areas mentioned previously, where the primary issue is output – perceiving and accessing materials from the screen – for individuals with physical limitations the issue is one of navigation and input. How do you move around a page or select links or controls if you cannot use a mouse or touchscreen? Individuals who lack the fine motor control for mouse use may rely on the keyboard alone to navigate and interact with controls on a computer or web page. Users with more severe hand or arm limitations may use voice recognition technology such as Dragon NaturallySpeaking to input text and to interact with controls and objects on a web page.
[@@@ sidebar - who else cannot access a mouse?]
Individuals who are blind and many with low vision cannot use a mouse to navigate a web page. Obviously, using a mouse requires the ability to see the mouse pointer and its interaction with objects on the screen. Therefore most screenreader users use the keyboard and keyboard commands to navigate and read web pages. Many websites use javascript to create pull down or fly-out menus which can only be accessed using a mouse. These types of menus are inaccessible to keyboard-only users. Therefore, there are a large amount of users – those with physical disabilities and those with vision impairments who will be locked out of pages that are not keyboard accessible. Keyboard access is a key component of accessibility and Universal Design.
[end sidebar]
The Importance of Keyboard Access
As mentioned in the sidebar (Who else cannot use a mouse), blind users and those without enough vision to follow the mouse pointer and target objects on a page also rely on keyboard access for navigation and control. Therefore, keyboard access is a crucial component of Web accessibility and, undisputedly, the most important component of accessibility for persons with upper extremity disabilities. or if they lack the fine motor control for mouse use, they may rely on the keyboard alone to navigate and interact with controls on a computer or web page.
[@@@ sidebar – try accessing a web page without a mouse]
Have you ever tried to access a website without a mouse or other pointing device? Certainly most of us have had the experiences of the mouse highlighting too much text or moving too fast up or down a page. The use of keyboard controls in these situations can be a more effective alternative. (Shift+arrow to highlight text for example).
Let’s try accessing a page without any use of the mouse. Go to <a href="http://www.colorado.edu">http://www.colorado.edu</a> or any page of your choice. If you are already open on a browser, you can use Ctrl+L (Windows) or Cmd+L (Mac) to move the focus to the address field. Enter the website address of your choice and press [enter] (or [return] on a Mac). Once your page loads, use the [tab] key to move through the page. Your cursor (or focus) should move through all the links and controls on the page. Depending on the browser and the styling for the page, you may see a dotted yellow or white line around each link on the page as you move through the page. The url of the link should also be visible at the bottom left of the page.
Pressing [enter] on a link should load that page. Backspace or alt+[left-arrow] will take back to the previous page. Here are some other useful keyboard commands:
Ctrl+[Home] – go to top of page.
Ctrl+[End] – go to end of page.
[down-arrow] – open up a pull down combo menu.
Try navigating through the page you chose and a couple of subpages. Are you able to navigate to all areas of the page; can you operate controls in search fields and in other control options?
[end sidebar]
[List other things you should do that we will cover in other parts of the book]
[highlight box:]
<a href="http://www.w3.org/WAI/intro/people-use-web/stories#reporter">Read a profile of an individual with a physical/mobility disability and their use of Assistive Technology</a>.
(Also read the section More about Mr. Martinez)
[end: highlight box]
Suggested viewing: Working Together: Computers and People with Sensory Impairments
To view a video of how individuals using different Assistive Technologies access computers and the Web, view the video at the url below.
<a href="http://www.washington.edu/doit/Video/index.php?vid=31">http://www.washington.edu/doit/Video/index.php?vid=31</a>
“Temporarily Able-Bodied” (TAB)
We're all getting older. We can't avoid it, can we? I look around, and I notice that a lot of us are getting gray. As we get older, we realize that disability is just a part of life. Anyone can join our group at any point in life. In this way, the Disability Rights Movement doesn't discriminate. So those of us who are temporarily able bodied and working for access and accommodations now get older, the changes they make will benefit them as well. - Ed Roberts, Co-founder of World Institute on Disability
Those on the side of the functional spectrum considered able-bodied (i.e. non-disabled) may consider this a permanent situation, but, as the title for this section reminds us, most individuals living a normal life span will at some point acquire a disability. Note that 97% of disabilities are acquired rather than congenital (present at birth) and the incidence of disability increases as we age.<a href="#_ftn8" name="_ftnref8" title="" id="_ftnref8"> </a> The reasons for this are self-evident: our senses diminish with age and we are more subject to degenerative diseases such as arthritis, cataracts, heart disease and stroke. Depending on the study cited, between 50%<a href="#_ftn9" name="_ftnref9" title="" id="_ftnref9"> </a> and 60%<a href="#_ftn10" name="_ftnref10" title="" id="_ftnref10"> </a> of individuals aged 65 or older in the U.S. have a disability and of those in the oldest age group – 80 or older - 70.5% have a disability and 55.8% have a severe disability.
The following statistics from the Census Bureau’s Americans with Disability: 2010 report highlights this:
- 1 in 20 individuals aged 15 – 24 had a severe disability.
- 1 in 4 individuals aged 65 to 69 had a severe disability.<a href="#_ftn11" name="_ftnref11" title="" id="_ftnref11"> </a>
- Those aged 65-69 have 5 times more likelihood of having a severe disability than those in the 15–24 age range;
- 70.5% of the oldest age group, 80 and older, had a disability, and more than half of this group (55%) had a severe disability, a rate of severe disability 10 times that of the 15 to 24 age group. (pg 5 & 6 of report for everything but the very last statistic).
Aging of Population
Regardless of whether you were motivated by the argument above, there’s another very strong argument for designing sites for using Universal Design and accessibility approaches: the population of the U.S., and the rest of the industrialized world in particular, is getting older. Since January 1, 2011, when the first baby-boomers turned 65 years old, 10,000 boomers turn 65 every day. This will continue until the end of 2030, when the last of the boomer cohort has reached 65.<a href="#_ftn12" name="_ftnref12" title="" id="_ftnref12"> </a> As a result, by 2030 19% of the U.S. population will be over 65 compared with 13% in 2010. By 3050, the percentage of the population over 65 will be twice as large as it was in 2010. The implications for disability are clear – we will very likely have a significantly increased percentage of those with disabilities. Therefore the need for websites, environments and products that are accessible will be both a social need and a marketable design skill.
<a href="#_ftnref1" name="_ftn1" title="" id="_ftn1"> </a> Americans with Disabilities: 2010, U.S. Census Bureau, pg. 4
<a href="#_ftnref2" name="_ftn2" title="" id="_ftn2"> </a> Census 2010
<a href="http://www.cdc.gov/nchs/fastats/disable.htm">http://www.cdc.gov/nchs/fastats/disable.htm</a> - Faststats - Center for Disease Control
<a href="#_ftnref3" name="_ftn3" title="" id="_ftn3"> </a> Ibid.
<a href="#_ftnref4" name="_ftn4" title="" id="_ftn4"> </a> Americans with Disabilities: 2010, U.S. Census Bureau, pg. 9
<a href="#_ftnref5" name="_ftn5" title="" id="_ftn5"> </a> <a href="http://www.cdc.gov/nchs/fastats/disable.htm">http://www.cdc.gov/nchs/fastats/disable.htm</a> - Faststats - Center for Disease Control
<a href="#_ftnref6" name="_ftn6" title="" id="_ftn6"> </a> <a href="http://lighthouse.org/about-low-vision-blindness/definition-legal-blindness/">http://lighthouse.org/about-low-vision-blindness/definition-legal-blindness/</a>
<a href="#_ftnref7" name="_ftn7" title="" id="_ftn7"> </a> This is not to say that the early Web was therefore a better or more accessible environment for all users. Individuals with learning or reading disabilities who benefit from multimedia and a graphical user interface (GUI) were at a disadvantage in this early environment.
<a href="#_ftnref8" name="_ftn8" title="" id="_ftn8"> </a> Goodley – disability Studies – pg. 1 (have 1st ch in pdf)
<a href="#_ftnref9" name="_ftn9" title="" id="_ftn9"> </a> Census 2010 - pg 17
<a href="#_ftnref10" name="_ftn10" title="" id="_ftn10"> </a> Altman B, Bernstein A. Disability and health in the United States, 2001–2005. Hyattsville, MD: National Center for Health Statistics. 2008. (SOURCE: CDC/NCHS, National Health Interview Survey.)
<a href="#_ftnref11" name="_ftn11" title="" id="_ftn11"> </a> Americans with Disabilities: 2010, pg. 5
<a href="#_ftnref12" name="_ftn12" title="" id="_ftn12"> </a> <a href="http://www.pewresearch.org/daily-number/baby-boomers-retire/">http://www.pewresearch.org/daily-number/baby-boomers-retire/</a>
