Types of Disabilities, Part 1

In my experience, disabilities have been categorized in many different ways. Most commonly, I’ve seen them generalized in the following 4 categories:

  • visual
  • hearing
  • mobility
  • cognitive

In their Introduction to Web Accessibility article, WebAIM is an example of one source I’ve found these 4 categories outlined. The University of Illinois at Urbana-Champaign‘s An Introduction to Accessibility and Inclusive Design class uses the same broad categories.

In contrast, Deque’s coursework addresses disabilities with more specific categories. They propose 13 categories altogether:

  • Blindness
  • Low Vision
  • Color Blindness
  • Deafblindness
  • Auditory Disabilities
  • Motor Disabilities
  • Cognitive Disabilities
  • Dyslexia/Reading Disabilities
  • Math Disabilities
  • Speech Disabilities
  • Seizure Disorders
  • Psychological/Psychiatric Disabilities
  • Multiple/Compound Disabilities

In comparison, the CPACC Body of Knowledge breaks disability types into 9 categories:

  • Visual
  • Auditory
  • Deafblindess
  • Mobility, flexibility, & body structure
  • Cognitive
  • Speech
  • Seizures
  • Psychological/psychiatric
  • Multiple/compound

So, for the sake of staying true to the study guide, let me tackle the first 4 on the CPACC list.

Visual

Visual disabilities can refer to blindness (of varying degrees), low vision, or colorblindness. Some of these communities prefer to be acknowledged as the specific disability (blind, low vision, or colorblind) rather than visually impaired. However, it’s better to ask someone about their preferred label, rather than assuming one voice speaks for everyone.

Blindness

According to legal definition, a person is blind if they have a visual acuity of 20/200 or less with correction or who has a field of vision (what can be seen in front of the person) of 20 degrees or less in their “best” eye. In 2017 the World Health Organization (WHO) estimated 1 million people in the US and 36 million people worldwide are legally blind.

Some causes of blindness:

  • Congenital
  • Cataracts
  • Diabetes
  • Macular Degeneration
  • Glaucoma
  • Accidents or traumatic injuries to the eye
  • Stroke
  • Retinitis Pigmentosa
Digital Environments
Challenge Solution
Digital interfaces with screens
  • Screen reader
  • Interface with built-in audio or speech
  • Refreshable Braille
Inaccessible content or interface (not compatible with screen reader)
  • Designers & authors can make markup for websites and content compatible with AT.
Physical Environments
Challenge Solution
Walking independently to places
  • White cane
  • Service animal
  • GPS-based walking instructions
  • Raised tiles on the ground
  • Obstructions removed from walkways and overhangs
Signage
  • Map & geolocation apps
  • Braille labels
  • Tactile models
Consumer Products
Challenge Solution
Flat interfaces and controls
  • Tactile controls
  • Audio interface
  • Mobile app control
Text on containers or packaging
  • Braille labels
Currency
  • Mobile app to read currency
  • Redesign of currency
  • Non-cash systems of payment
Printed materials (text and images)
  • Optical character recognition software
  • Conversion to digital format
  • Conversion to Braille

Additional Reading about blindness:

Low Vision

A person is considered to have low vision if their vision is 20/70 or poorer in their best eye with correction. People with low vision often struggle to accomplish visual tasks, but with the use of assistive technologies or adaptive strategies, they sometimes can accomplish those tasks. The National Institutes of Health estimates that there are 2.9 million people in the US and 246 million worldwide with low vision.

Types of low vision:

  • blur (generalized haze)
  • blur with low contrast (generalized haze)
  • cataracts (generalized haze)
  • diabetic retinopathy (central vision)
  • glaucoma (central vision)
  • hemianopia (peripheral vision)
  • macular degeneration (central vision)
  • retinal detachment (peripheral vision)
  • aphakia (generalized haze)
  • light sensitivity
  • night blindness
Physical and Digital Environments
Challenge Solution
Small text
  • Screen magnifier
  • Software or settings to increase contrast
  • Screen reader
  • Interface with built-in speech
  • Large print
  • Digital format compatible with AT
Low contrast
  • Software or settings to increase contrast
  • Designers and content creators choose high contrast for readability

On Day 51 of my WAS certification exam journey., I posted about Users with Low Vision, which expands on some of this information.

Colorblindness

Colorblindness is the inability to distinguish between certain kinds of colors, based on brightness and luminosity. 1 in 12 men and 1 in 200 women worldwide experience colorblindness.

Types of colorblindness:

  • red-green, including red on black (Deuteranopia and Protanopia)
  • blue-yellow (Tritanopia)
  • grayscale (Achromatopsia)
Physical and Digital Environments
Challenge Solution
Color combinations with low contrast
  • Designers shouldn’t depend on color only to share information

Auditory

Auditory disabilities range from mild to profound hearing loss and deafness. Some causes of auditory disabilities:

  • genetics
  • congenital
  • premature birth
  • infections/illnesses
  • ear trauma
  • exposure to loud noises
  • aging
Digital Environments
Challenge Solution
Audio
  • Full transcript
  • Sign language interpretation
Video
  • Synchronized captions
  • Full transcript
  • Sign language interpretation
Physical and Digital Environments
Challenge Solution
Speeches or presentations
  • Sign language interpretation
  • Live captions
Physical Environments or Consumer Products
Challenge Solution
Doorbells or other alarms
  • Visual alerts
  • Tactile alerts

Deafblindess

Deafblindness is a combination of blindness and deafness. People who are deafblind encounter the same challenges as blind and deaf people would.

Digital Environments
Challenge Solution
Text or images
  • Screen reader with refreshable Braille output
Video and/or audio
  • Full transcript

Mobility, flexibility, & body structure

People with mobility impairments may experience difficulty moving, controlling, or coordinating movements of the body. Some of these disabilities subcategorized as traumatic injuries (spinal cord injury, stroke, damage to limb) or biological conditions (CP, MD, Parkinson’s, MS, ALS, RA).

Causes of mobility impairments may be due to:

  • genetics
  • premature birth
  • illnesses
  • accidents
  • aging
Digital Environments
Challenge Solution
Mouse
  • Other input devices: keyboard, alternative keyboard, mouth stick, head wand, switch device,
    speech recognition, eye tracking
  • Developers and designers ensure keyboard (and other input devices) operability
Timed sessions
  • Designers can delay timeouts
  • Designers can provide alerts for timeout
  • Designers can allow time extension
Physical Environments
Challenge Solution
Steps and escalators
  • Ramps
  • Elevators
Small spaces
  • Wider spaces for wheelchair access
  • Remove obstacles in pathways
General
Challenge Solution
Walking
  • Walker
  • Cane
  • Crutches
  • Braces
  • Wheelchair
  • Scooter
Door knobs, handles, entrances
  • Door actuators
  • Motion sensors to automate door
  • Lever handles

Additional reading about motor disabilities:

To Be Continued…

This post only covers touches on some of the categories of disabilities. Next up, I’ll be learning about cognitive, speech, seizure, psychological/psychiatric, and compound disabilities to share with you in Part 2.

6 Theoretical Models of Disability

In my last post Basic Disability Concepts, I mentioned that we all need a perspective check when we design websites and start thinking about people with disabilities. Turns out that there are many different theoretical models that have been proposed on this very topic of how we perceive disabilities! I’ve encountered a couple of these before, thanks to Sarah Horton’s and Whitney Quesenbery’s book A Web for Everyone (Amazon).

The models I cover in this post:

  1. medical,
  2. social,
  3. economic,
  4. functional solutions,
  5. social identity, and
  6. charity.

There are more than 6 models that have been theorized, but I only offer them a mention, and provide resources at the end to get you started on your own research.

Medical

The medical model (perspective) views disability as a medically-diagnosed biological problem due to genetic disorders, disease, trauma, or other health conditions. Law leans this definition to critically evaluate whether a person is impaired “enough” to receive benefits or accommodation. The person has a problem that needs to be cured or fixed.

Strengths:

  • emphasizes the biological
  • offers criteria for medical treatment and legal evaluation
  • belief that a compassionate society will invest in health care and services to support disabilities

Weaknesses:

  • overlooks impact of design decisions (it’s the person’s problem, not the environment)
  • stigmatizes people as different or second-class citizens
  • can create narrow and exclusive definitions
  • dehumanizing if a person has to prove their disability

Social

The social model (perspective) views disability as a condition created by bad design. Society’s ecosystem institutes barriers for people. It’s in response to the medical model, and rallies for change in the culture and ideology of society to be more inclusive.

Strengths:

  • emphasizes the human right to participate in society
  • removes stigma
  • inspires creative design

Weaknesses:

  • de-emphasizes biological reality of a disability
  • strips disability from a person’s identity

Economic

The economic model (perspective) views disability as the inability of a person to work and contribute to society. It’s related to the Charity/Tragedy model.

Strength:

  • emphasizes the need for economic support or accommodation

Weaknesses:

  • disabled become stigmatized as needy
  • narrow definition may deny help to a person who needs it but doesn’t meet qualifications

Functional Solutions

The functional solutions model (perspective) views disability as problem to be solved. Specifically, it seeks to overcome physical limitations with technology. It cares less about the social or political nuances, but rather strives for innovation as its motivation. Accessibility professionals often live in this space.

Strengths:

  • meets people where they are
  • service-based
  • focused on solutions
  • real-world approach

Weaknesses:

  • myopic (doesn’t address broader issues)
  • misses opportunities of social change

Social Identity / Cultural Affiliation

The social identity or cultural affiliation model (perspective) views disability as a community. People who identify with a particular group or culture (e.g. deaf culture) become more involved with that culture and embrace their disability as part of their identity.

Strengths:

  • disability is accepted and even a point of pride
  • groups find political strength to advocate for change

Weaknesses:

  • sense of exclusion when a person doesn’t fit the mold or expectation of the group
  • alienation from society when involved with a specific group

Charity/Tragedy

The charity or tragedy model (perspective) views disability as tragic, unfortunate, or inspirational. When this perspective becomes an attitude, it can become offensive to people with disabilities.

Strength:

  • inspires fundraisers, projects, assistance, and intervention for people with disabilities

Weaknesses:

  • creates an unhealthy social relationship or hierarchy
  • condescending or dehumanizing
  • perpetuates the lie that people with disabilities are objects of inspiration (inspirational porn)
  • short-term

Other Models

In addition to the models I’ve dissected in this post, there were other honorable mentions in the CPACC coursework I’m working through; all of which have their own merits and pitfalls.

  • Affirmation: similar to the social identity model, it views disability as an chance to affirm one’s identity and celebrate that part of self;
  • Sociopolitical: views disability needs as a human right;
  • Religious/moral: views disability as an act of God to punish or teach;
  • Expert/professional: a variation of the medical model, it views disability as a condition to be treated or managed by experts;
  • Rehabilitation: a variation of the medical model, it views disability as a condition to be treated be therapy and rehabilitation;

Are you familiar with any other models that haven’t been mentioned here?

Where Do You Stand?

I don’t know about you, but all these models have given me a lot to think about, challenging my own perspective and world view. The variety of definitions have offered some confirmation on thoughts I’ve had. In contrast, they’ve pointed out some of my own fault in thinking about myself and others.

In order to do the work of advocating for people with disabilities and developing websites with accessibility in mind, we need to understand our own point of view. Believe it or not, our work is colored by our current perspective. Before we can have conversations with people with disabilities, we need to evaluate where we stand and what language we use.

What does “disability” mean to you?

Resources I Found Helpful

Basic Disability Concepts

My first CPACC study session involved me reading through Deque’s “Basic Disability Concepts” section. I completed that in less than an hour, and took that extra time I had to start reviewing IAAP’s CPACC Body of Knowledge Word document. Within that document, I didn’t see an equivalent of the overview that I went through on Deque, but that wasn’t surprising since it was basically a perspective check before wading into the rest of the material. Though it was a short section, I still found several bits interesting, if not eye-opening.

Our diverse abilities

I think we all have some preconception of what a disability looks like. However, there’s often more to it than our own limited perspective. Did you know that 20% (1/5) of people have some form of disability, whether permanent or temporary? Alaska statistics seem to support that number wholeheartedly with 21.9% of Alaskans over 18 years of age who have a disability [Centers for Disease Control and Prevention].

In that vein, we may ask, “Are there really that many blind folks or people in wheelchairs?” However, some disabilities are not so obvious to us. We may not realize that there are people in close proximity who are deaf, have a reading disorder, experience seizures, or are colorblind. They are not wearing a sign or shouting to be noticed for their disability, if they even identify as having a disability.

Why would users of the web be any different? When creating content and experiences for the web, we should be considerate of people with:

Accessibility matters

Once we understand that a not-so-insignificant number of people have a disability and that those categorized disabilities vary in form and spectrum, we can better understand why accessibility matters. Our next step is to not make assumptions and meet people where they are. Did you know that less than 10% of blind Americans can read braille? This was one of the more surprising statistics I read, so naturally I went down the rabbit hole of searching for a 2009 National Federation for the Blind online report that offered that statistic. (I was unsuccessful.) However, this statistic is a good example of why we can’t make assumptions about people, if we want to be part of the solution to enable people with disabilities to independently make choices and take action.

Assistive technologies

As a web designer and developer, I should understand that there are many different types of assistive technologies (AT) to help people with disabilities independently access the content my website has to offer. Sometimes one AT can be used by several disability groups, even ones you wouldn’t expect. See any AT that you use to make accessing content easier for you?

Assistive Technology Disability
screen readers
  • blindness
  • low vision
  • cognitive disabilities
refreshable Braille display
  • blindness
screen enlargers (magnification, zoom)
  • low vision
color overlays
  • color blindness
  • cognitive disabilities
captions
  • deafness
transcripts
  • deafness
head wand
  • motor/mobility disabilities
mouth stick
  • motor/mobility disabilities
alternative keyboards
  • motor/mobility disabilities
eye gaze tracking
  • motor/mobility disabilities
voice activation
  • motor/mobility disabilities
augmentative communication aids
  • cognitive disabilities

By the way, AT takes on many forms and does many things, but AT can also be misunderstood.

  • AT isn’t restricted to people with disabilities. It is available to everyone. People who don’t have low vision can benefit from glasses. Parents pushing strollers can benefit from elevators.
  • AT isn’t magical. It can’t overcome barriers that were created from the start. If a website isn’t built with accessibility in mind, it’s not going to become magically accessible when a screen reader is turned on or an “accessible” overlay tool is lobbed on.

The Digital Accessibility Revolution

It’s important to recognize that the web isn’t the problem, but rather an important part of the solution to empower people with disabilities. Consider these situations:

  • a blind person wants to independently access the latest news, or
  • someone with a mobility impairment prefers to shop online because it’s easier than taking a trip to a brick and mortar mall

The idea about us designers and developers creating a problem was impactful enough for me to post on Twitter:

Perspective check

In conclusion of this brief overview of my coursework, it’s all about readjusting and widening our perspective when we offer a service to people. Without that perspective check, we can’t possibly absorb additional information about other people around us and the challenges they face on a daily basis. Without understanding, there is no meaningful advocacy and no motive for a culture of inclusion. And with that, your business or organization is left with a narrowed mission and weaker service because only some people are allowed at the table. Even Mother Nature knows that diversity makes the ecosystem stronger.