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AskTog, April 2009

Inclusive Design, Part 1

With Some Shocking Revelations About Your Future

Have you ever thought about what it would be like to be disabled? Well, you better start thinking about it!

As my collegue Gregg Vanderheiden is fond of pointing out, “We all will have disabilities eventually, unless we die first.”

(Russian translation:

Пост доступен на сайте Объединяющий дизайн на мобильных устройствах и ПК.)

The Arc of Disability

Particularly in the US, people think of disabled people as a separate class of “unfortunates.” The truth is that not only will all of us start experiencing disabilities with age, we start out effectively disabled, a mewling, puking creature unable to perform the simplest acts that adults handle routinely. Our level of disability then typically decreases until age 16, when we are considered legally able to command our society’s dominant form of transportation, the automobile.

The only periods of disability most of us will experience between 16 and 45 are the result of voluntary behavior. Characterized by cognitive and vestibular impairment, one cluster of episodic disabilities tend to occur on either Friday or Saturday nights. By age 22 or so, these either start to lessen or we eventually land in AA. Both alchohol and testosterone can lead to other more persistent periods of disability involving splints, casts, or traction. Still, from 16 to 45, most of us have clear sailing, our only consistent disability being an inability to appreciate the limitations of others.

At around age 45, our eyesight begins to weaken as our ability to focus near and far becomes limited (presbyopia) and our vision literally begins to dim.

Our hearing starts to go as presbycusis kicks in at around age 65 or so (unless we were Led Zeppelin fans, in which case it started to go by our late teens). Mild presbycusis primarily affects the consonant range of frequencies, resulting in speech seeming as loud as ever, but being less intelligible. This, as well as other drops in perceptual faculties, results in younger people assuming we’re growing more stupid, when, in fact, we may be just as sharp as ever, but receiving less data from our surroundings.

By age 80, we have begun to experience the reverse of our arrival, with driving privileges threatened with suspension, and general mobility and cognitive abilities decreasing as we approach end of life.

We all thus experience an arc of disability in our lives, dust to dust, diapers to diapers.

Spectrum of Disabilities

Whereas "arc" describes the varying level of disabily everyone experiences as we age, "spectrum" pertains to the level of disability a person might experience at any given moment. Different people develop differing levels of disability, thus making it a spectrum, rather than a binary either you got one or you don’t. Vision disabilities, for example, stretch from the mildest impairment to the most profound—total blindness—but there are many intermediate steps along the way.

We are perhaps most well versed in the needs of people who are totally blind and appreciate the need to provide screen readers, etc., to aid their use of computers, but there are also millions of people are “legally blind,” still able to see under certain conditions.

An example is the great 20th Century cartoonist, James Thurber. He was injured while playing William Tell with his brother. He, unfortunately, was the one holding the apple on his head, and his brother, bless his heart, was not much of a shot. That little incident cost him one eye, and the other soon began to fail as well. Failing eyesight did not dampen his enthusiam for the cartoon, however, and, for much of his career, he drew cartoons life-size on giant sheets of paper. Computer operating systems today afford people who are legally blind the ability to blow up the image on their display to a size equivalent to a giant sheet of paper.

At the opposite end of the spectrum are the gradual limitations of eyesight that hit all of us at around age 40. They are not nearly as swift or as serious as being hit in the eye with an arrow, but they result in a disability nonetheless, though one that, for most of us, can be corrected with a drugstore pair of reading glasses. Presbyopia may lie far down the spectrum from total blindness, but young designers who use tiny fonts pleasing to their eyes may be creating web pages that a large percent of their users will either be uncomfortable with or unable to read entirely, at least without a return trip to the drugstore to buy more powerful glasses.

User observation with a variety of age groups and differing expected levels of disability are the way to discover whether your site, software, or product is going to work across the entire spectrum of disabilities before you ship it.

Temporary vs. Permanent Disabilities

Disabilities can be either permanent or temporary. Right now, I’m only left handed, having, as the high-powered neurosurgeon I consulted put it, “twanged” the nerve in my right arm. The injury ocurred while I was carrying out an experiment involving a large body accellerating at 32 feet per second per second being brought to rest suddenly and violently by the large body’s hand grabbing hold of a ladder rung at the last possible moment. Twang! The injury has made me intensely aware of limitations of my Macintosh laptop that has all kinds of cables and giant video adaptors sprouting out of the left side of the computer to cover the top half of my mousepad, blocking the mouse at every glide.

Imposed Disabilities

Our society, through our choice of technologies, has created entire classes of people who are, in essence, disabled. No, we haven’t crippled them, but we’ve built elaborate infrastructures that depend on abilities that we know many people will not have for the course of their lives, abilities that they didn’t need to succeed in earlier centuries.

The largest disenfranchisement surrounds the automobile. Before the car, people typically lived where they worked. If they lived elsewhere, they were within easy walking distance. The automobile changed that, with people from 16 to 80 able to live anywhere they liked and drive anywhere they wanted.

In the US, entire cities, like Los Angeles, were built with the assumption that every citizen would be able to drive. Sprawling, low-density housing and remote stores and workplaces ensured that those unable to drive must endure childlike dependency on those who could. The majority of voters—those between 18 and 80—drove all over the needs of the minority, leaving both the old and young with few options.

The cost of ownership of a car, from purchase price to fuel, to upkeep, to transportation taxes, to environmental costs, etc., is extremely expensive, but this tyranical majority has come to accept it and will scream bloody murder when someone wants to squander taxpayer money on public transportation for those millions left hanging.

The automobile was not our first imposed disability. Print was an earlier one. People over 40 were doing just fine in society before the advent of the printing press. Sure, if you had been a scribe in your younger days in the monestary, you might end up being put out to pasture—or at least forced to work in the pasture—but, for most people, not being able to see up close was not a crushing limitation. All of a sudden, as print gained in prominence, people reaching middle age lost what society had adopted as a critical communication ability.

Computers have likewise imposed limitations that have forbidden millions of people to enjoy the fruits of the cyberspace revolution. These limitations have grown fewer over time. When I first became involved with computers, the ability to solder was an absolute requirement. Then, one only had to be able to program. Eventually, everyone with good eyesight, fully-functioning limbs, and the ability to construct complex mental models was invited to the party. The advent of the graphical user interface and standard accessibility features, such as sticky keys and visual Zooming, opened up admission even further.

Sometimes, restrictions are necessary: If you are designing software for air traffic controllers, a rich graphical environment is a necessity if the controllers are to keep planes from occupying the same space at the same time. If, however, you’ve designed a piece of software that arbitrarily depends on changing an object from red to green to indicate state, you have just killed off the 7% or so of your potential male users who have red-green color blindness, and you are officially a bad person.

Accessibility Specialists

Accessibility specialists are the ones who came up with the idea of curb cuts, so that people in wheelchairs could cross the street. They’ve provided a lot of little add-ons to computers, too, such as a sticky-key mode for people who can only touch one key at a time, so they can tap Shift, then subsequently press Q to get an upper-case Q.

This little closed system of specialists addressing the needs of the seriously disabled has relieved the rest of us of having to even think about the needs of people not like us.

Bad idea.

First, accessibilty specialists spend most of their time running around trying to clean up our messes, messes we often imposed on people because we just didn’t think through what we were creating in the first place.

Second, accessibility people focus so exclusively on the seriously disabled that they often inadvertantly block the rest of us from great solutions that would alleviate a much broader group’s limitations. Here's what can happen when accessibility specialists failed to cut the rest of us off.

Case Study: An Accidental Success

A little start-up in 1990 decided to focus exclusively on the specific needs of people with arthritis. Their users’ problem? Pain. The solution? Tools that would distribute contact between tool and user over a large enough area to relieve pressure on both the soft tissues as well as inflamed joints, then would require minimum strength at any given moment to use the device through its full range of motion.

What tools do most people use every day? Tools in the kitchen. That’s where they focused their attention. They called their tools, “Good Grips,” and they named their company OXO. It turned out that comfortable, attractive tools are enjoyed by a lot of people who don’t have arthritis, and OXO became a wild success.

Inclusive Design

What OXO did was to create tools that everyone, not just a limited subset of people, loves and can use. Those that that studied their sucess, like simplehuman®, followed in their footsteps, creating products that would be attractive to a fullest spectrum of potential users possible. Such an approach is now called “inclusive design.” It not only helps build rich markets for new technologies, but can open whole new markets for old technologies.

SMS messaging in the US used to be pretty much the domain of teens, tweens, and geeks, given the weird form of typing involved as well as the limited display. The iPhone, with its clear, cartoon-bubble dialog display and its full ASCII keyboard, made a powerful technology accessible to millions of people who might have been able to use the previous technology if pressed, but were unwilling to do so voluntarily. (Europe, with its confiscatory pricing of phone calls and cheap or free SMS, forced the unwilling to use a technology they didn’t really favor.)

People uncomfortable with learning SMS are pretty low on the disability spectrum, but identifying and addressing a simple lack of comfort can often jump profits even more than hitting the middle or end of the spectrum.

The Low-End Trap

A fear of poor financial return for addressing the needs of the seriously disabled often leads companies to limit their human-machine-interaction efforts to just the low end of the spectrum, aiming just to make the fully-abled comfortable.

In Karate, they teach their students, when wanting to strike their opponent's stomach, to not to aim for the stomach, but the backbone behind the stomach. They could never actually reach there, but this goal ensures they are at maxium velocity when they do reach the stomach.

When a company's goal is to just make a product comfortable to the fully-abled, the effort will almost instantly degrade to just making sure people can at least use the stupid thing.

By aiming high, really high, you not only will end up with products that are responsive to the needs of the seriously disabled, you’ll have products, like OXO’s, that go well beyond barely-usable to truly delightful, the kind of products that users go out of their way to tell their friends about. Products like the iPhone, for example.

If we think of the entire spectrum of disability, from mild discomfort to catastrophic disability, we will come up with inclusive solutions that will not only level the playing field for society, but attract a lot more people into the game.

Next month in Part Two: How to organize for and achieve inclusive design.


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