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<h1>Chapter 11: Web Accessibility & Users</h1>
* Accessibility Overview
* The 4 major areas of disability
** Mobility
**	Vision
**	Cognitive
**	Hearing 


<p>Quotes:</p>
<p>[add Cerf quote or  another quote about people with disabilities using the web]<br />
  &ldquo;People sometimes ask  me, &lsquo;What about accessibility? Isn&rsquo;t that part of usability?&rdquo; – Steve Krug</p>
<ul>
  <li>Accessibility Overview</li>
  <li>Disability Statistics</li>
  <li>The 4 major areas of disability</li>
  <ul>
    <li>Mobility</li>
    <li>Vision</li>
    <li>Cognitive</li>
    <li>Hearing </li>
  </ul>
</ul>
<p>&nbsp;</p>
<h1>Accessibility  Overview</h1>
<h2>What do we mean by accessibility</h2>
<p>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 &ldquo;Web accessibility,&rdquo; then review statistics on disability in the  U.S.; discuss the particular access issues for each disability area; and  finally, we will discuss demographic trends in the U.S. and elsewhere related  to aging and consider how this informs our discussion of Universal Design.</p>
<h3>Web Accessibility vs. Usability</h3>
<p>            Earlier, [I  think – check on this], we discussed the differences and similarities between the  concept of Web accessibility and usability. And Steve Krug asks the question  directly in the second quote above – to paraphrase – accessibility a part of  usability, is it not? <br />
  What do you think? Let&rsquo;s look at the definitions of both  terms before answering. To answer this we need to first define our terms.<br />
  Jacob Nielson defines  usability as a&nbsp;&ldquo;<strong>quality attribute</strong><strong>&nbsp;</strong>that assesses how easy user  interfaces are to use.&rdquo;&nbsp; (Nielson - <a href="http://www.nngroup.com/articles/usability-101-introduction-to-usability/">http://www.nngroup.com/articles/usability-101-introduction-to-usability/</a>)<br />
  The ISO definition,  mentioned in chapter 1, is &quot;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.&quot;<br />
  Accessibility, on the other hand, is the design of  products, interfaces and environments so that it can be used by people with a  wide range of abilities, including those with disabilities. If Web  accessibility is primarily about making sites usable by persons with  disabilities, are we therefore talking about a special population? That 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. [Put in quote from lab at AHEAD]. 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.<br />
  Therefore we need to understand the needs of our wider  audience. That&rsquo;s what we will do for the rest of the chapter: focus on audiences  with &ldquo;special needs,&rdquo; 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. Now let us begin our discussion of disability demographics.<br />
</p>
<p>&nbsp;</p>
<ul>
  <li>Disability Statistics</li>
</ul>
<p>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. </p>
<p>[Sidebar – problems with disability  statistics]<br />
  One of the things that become noticeable (and frustrating)  when referencing statistics on disability is the variation found between  different studies. For example, the Census Bureau report <em>Americans with Disabilities: 2010 </em>measures the prevalence of vision  disability at about 8.1 million or 3.3%, significantly lower than the Center  for Disease Control estimate – 21.2 million - used above. Why the difference?  How disability is defined, the way questions are asked, sampling methods and  sizes and other factors can affect statistical outcomes. <br />
  Disability is not a binary (yes or no) determination, in  contrast to measurements such as age or height and weight. If we know someone&rsquo;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 disabled. <br />
  [end sidebar]</p>
<h2>Domains of Disability</h2>
<p>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. </p>
<p>&nbsp;</p>
<table border="1" cellspacing="0" cellpadding="0">
  <tr>
    <td width="202" valign="top"><p>Disability Category</p></td>
    <td width="195" valign="top"><p>Number of Individuals</p></td>
    <td width="193" valign="top"><p>Percentage    of Population</p></td>
  </tr>
  <tr>
    <td width="202" valign="top"><p>Vision<a href="#_ftn2" name="_ftnref2" title="" id="_ftnref2"> </a></p></td>
    <td width="195" valign="top"><p>8.1 million</p></td>
    <td width="193" valign="top"><p>3.3%</p></td>
  </tr>
  <tr>
    <td width="202" valign="top"><p>Physical/Mobility<a href="#_ftn3" name="_ftnref3" title="" id="_ftnref3"> </a></p></td>
    <td width="195" valign="top"><p>37.4 million</p></td>
    <td width="193" valign="top"><p>16.2%</p></td>
  </tr>
  <tr>
    <td width="202" valign="top"><p>Mental    or Cognitive Disability<a href="#_ftn4" name="_ftnref4" title="" id="_ftnref4"> </a></p></td>
    <td width="195" valign="top"><p>10.6 million</p></td>
    <td width="193" valign="top"><p>4.4%</p></td>
  </tr>
  <tr>
    <td width="202" valign="top"><p>Hearing    Disabilities<a href="#_ftn5" name="_ftnref5" title="" id="_ftnref5"> </a></p></td>
    <td width="195" valign="top"><p>7.6 million</p></td>
    <td width="193" valign="top"><p>3.1%</p></td>
  </tr>
</table>
<p>Let us look at each of these disabilities in more depth.  [Need better transition, lead in]</p>
<h3>Vision</h3>
<p>Vision impairments include blindness  [include specific definition of legal blindness in footnote, elsewhere?], low  vision or color blindness. Low vision, as defined by the Census 2010 survey is &ldquo;having  difficulty seeing words and letters in ordinary newsprint, even when wearing  glasses or contact lenses&rdquo; (pg. 8 Census 2000). Note that this definition of <em>low vision</em> is rather narrow – for  example, color blindness would not be included under the Census survey&rsquo;s  definition of <em>low vision</em>. In  addition, reading from a paper medium 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).</p>
<p>&nbsp;</p>
<h3>Hearing</h3>
<p>Hearing impairments include deafness or  difficulty hearing. Difficulty hearing is defined as &ldquo;difficulty hearing a  normal conversation, even when wearing a hearing aid&rdquo; (pg. 8. Census 2010).</p>
<p>&nbsp;</p>
<p>&nbsp;</p>
<h3>Cognitive/Intellectual</h3>
<p>            A  cognitive/intellectual disability can range from perceptual/cognitive issues  such as dyslexia to ADHD to memory loss to dementia.</p>
<h3>Physical/Mobility</h3>
<p>            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. </p>
<h2>Accessibility Issues by Disability    </h2>
<p>&nbsp;</p>
<h2>Vision</h2>
<p>            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. (Mention sidebar of initial Web). </p>
<p>            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 &ldquo;no.&rdquo; Screenreader technology such as JAWS (Windows) or VoiceOver  (Mac) allow voice output (the &ldquo;reading&rdquo; of screen text with synthesized speech)  for individuals who cannot see or read the text or other objects on the screen. </p>
<p>            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 the screen, whether a web page or the desktop of the computer.<br />
  [Highlight box]<br />
  <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.<br />
  (Note: the site opens with the section <em>More about Ms. Laitinen </em>closed by default. Be sure to open us this  section. Similarly the section <em>Text  alternatives for non-text content (Perceivable) </em>under <em>Sections related to Ms. Laitinen</em>.)<br />
  [end:  highlight box]</p>
<h4>What Can Be Read by a Screenreader? The Importance of Alternative Text.</h4>
<p>            Although  screen enlargement software can enlarge both text and images, screenreader  technology can read text and <em>only</em> images  that that have been marked up with alternative text (in the context of HTML  referred to as the &ldquo;alt attribute&rdquo;). Alternative text is a short description of  the purpose of, or the information conveyed by, the image (will be discussed  further in ….???).<br />
  [sidebar: Google is deaf and blind billionaire]</p>
<p>            Alternate  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 &ldquo;findable&rdquo; with Google, Yahoo, and  other search tools.<br />
  [List other things you should do that we will cover in other  parts of the book]</p>
<h4>Hearing</h4>
<p>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="#_ftn6" name="_ftnref6" title="" id="_ftnref6"> </a> With the rise of audio and multimedia on the Web, the likelihood of Deaf and  Hard of Hearing individuals encountering content that they cannot access has  significantly increased, particularly in the last decade.<br />
  [find out when audio and multimedia  first appears on the Web]<br />
  For those with deafness or hearing  loss, access to audio is provided through transcripts (for content which is  exclusively audio) and captioning (for multimedia). 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.<br />
  [List other things you should do that we will cover in other  parts of the book]<br />
  (Other benefits of captioning)</p>
<p>[highlight box:]<br />
  <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>.<br />
  (Also read the section <em>More about Ms. Olsen</em>)<br />
  [end: highlight box]</p>
<p>&nbsp;</p>
<h4>Cognitive/Intellectual</h4>
<p>            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  following of best design practices also benefits both these groups (and all  users for that matter).                        [need to reword]<br />
  [List other things you should do that we will cover in other  parts of the book]</p>
<p>[highlight box:]<br />
  <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>.<br />
  (Also read the section <em>More about Ms. Olsen</em>)<br />
  [end: highlight box]</p>
<h4>Physical/Mobility</h4>
<p>            Individual  with physical or mobility disabilities affecting their upper extremities (i.e.  their arms) 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). Individuals  with upper extremity limitations may use voice recognition technology such as  Dragon NaturallySpeaking to input text and to interact with controls and  objects on a web page; 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.<br />
  [List other things you should do that we will cover in other  parts of the book]<br />
  [highlight box:]<br />
  <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>.<br />
  (Also read the section <em>More about Mr. Martinez</em>)<br />
  [end: highlight box]<br />
  Suggested viewing:  Working  Together: Computers and People with Sensory Impairments<br />
  To view a video of how individuals using different Assistive  Technologies access computers and the Web, view the video at the url below.<br />
  <a href="http://www.washington.edu/doit/Video/index.php?vid=31">http://www.washington.edu/doit/Video/index.php?vid=31</a></p>
<p>&nbsp;</p>
<p>statutory/legal blindness continues to be defined as best corrected  visual acuity of 20/200 or less in the better eye; or a visual field limitation  such that the widest diameter of the visual field, in the better eye, subtends  an angle no greater than 20 degrees (<a href="http://lighthouse.org/about-low-vision-blindness/definition-legal-blindness/">http://lighthouse.org/about-low-vision-blindness/definition-legal-blindness/</a>)<br />
</p>
<p>&nbsp;</p>
<p> </p>
<h4>&ldquo;Temporarily Able-Bodied</h4>
<p>Those of us on the side of the functional spectrum  considered able-bodied (i.e. non-disabled) may consider this a permanent  situation, but in all likelihood this will change as you age, although  hopefully later than sooner. <br />
  The Census Bureau&rsquo;s <em>Americans  with Disability: 2010</em> report offers these other rather interesting  statistics:</p>
<p>&nbsp;</p>
<ul>
  <li>1 in 20 individuals aged 15 – 24 had a severe  disability. </li>
  <li>1   in 4 individuals aged 65 to 69 had a severe disability. <a href="#_ftn7" name="_ftnref7" title="" id="_ftnref7"> </a></li>
</ul>
<p>&nbsp;</p>
<ul>
  <li>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.  (pg 5 &amp; 6 of report).</li>
</ul>
<p>&nbsp;</p>
<h2>Aging of Population</h2>
<p>Although we saw that  there are differences in how various studies measure disability, one  thing is indisputable when looking at disability statistics: disability  prevalence increases with age. Clearly, as we age, our chances of acquiring a  disability increases. The reasons for this are self-evident: our senses  diminish as we age and we are more subject to degenerative diseases such as  arthritis, diabetes, cataracts, heart disease and stroke. [There is a saying  among the field of disability: someone either has a disability or are  &ldquo;temporarily abled.&rdquo; [find source]] In other words, almost all of us will  eventually experience a disability either through disease, accident, or the  normal process of aging. (Are you depressed yet?).<br />
  Even if you are one of the lucky people to die peacefully in  your bed at a ripe old age without experiencing any loss of physical, sensory,  or cognitive function (highly unlikely), it still behooves you to learn and  incorporate UD into your Web design tool kit. </p>
<p>If we look at the prevalence of disabilities across age  groups, we clearly see that disability increases with age – those aged 65-69  have 5 times more likelihood of having a severe disability than those in the 15–24  age range; those 80 and over have 10 times the likelihood. With the aging of  the baby-boomers, by 2030, 19% of the population will be over 65 compared with  13% in 2010. The implications for disability are clear – we will very likely  have an significantly increased percentage of those with disabilities.</p>
<p>As we discussed in chapter 1, the aging of the population is  part of the impetus for Universal Design.</p>
<p>[Include World Wide Stats]</p>
<p>&nbsp;</p>
<p>&nbsp;</p>
<div>
  <div id="ftn1">
    <p><a href="#_ftnref1" name="_ftn1" title="" id="_ftn1"> </a> <em>Americans with Disabilities: 2010</em>, U.S.  Census Bureau, pg. 4</p>
  </div>
  <div id="ftn2">
    <p><a href="#_ftnref2" name="_ftn2" title="" id="_ftn2"> </a>  Census 2010<br />
      <a href="http://www.cdc.gov/nchs/fastats/disable.htm">http://www.cdc.gov/nchs/fastats/disable.htm</a> - Faststats - Center for Disease Control</p>
  </div>
  <div id="ftn3">
    <p><a href="#_ftnref3" name="_ftn3" title="" id="_ftn3"> </a> Ibid.</p>
  </div>
  <div id="ftn4">
    <p><a href="#_ftnref4" name="_ftn4" title="" id="_ftn4"> </a> <em>Americans with Disabilities: 2010</em>, U.S.  Census Bureau, pg. 9</p>
  </div>
  <div id="ftn5">
    <p><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</p>
  </div>
  <div id="ftn6">
    <p><a href="#_ftnref6" name="_ftn6" title="" id="_ftn6"> </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. </p>
  </div>
  <div id="ftn7">
    <p><a href="#_ftnref7" name="_ftn7" title="" id="_ftn7"> </a> Americans with Disabilities: 2010, pg. 5</p>
  </div>
</div>




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