Usability meets accessibility

Where usability meets accessibilityWhitney Quesenbery, Center for Civic DesignJayne Schurick, Knowbility

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Hi!

WhitneyUser research, plain language, usability

Found accessibility through work on civic design and elections.

JayneUsability

Found accessibility through Phillip Morris.

3Our starting point: user experience and the user-centered design process

1. Understand people and context

of use2. Identify requirements

3. Explore design solutions

4. Evaluate with users

Source: ISO 9241-210 (formerly ISO-13407)

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Accessibility and usability go hand in hand

Usability

The effectiveness, efficiency and satisfaction with which a specified set of users can achieve a specified set of tasks in a particular environment.

– ISO 9241-11

Accessibility

The usability of a product, service, environment or facility by people with the widest range of capabilities

– ISO 9241-20

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Accessibility error priorities

1. CriticalAn absolute barrier to access

2. SeriousA barrier that could cause frustration to most and be a barrier to some, causing a need for work-arounds

3. ModerateA frustration that would not prevent someone from using the site

4. MinorA WCAG error that is unlikely to cause problems

- Glenda Sims, Deque

Source: 2103 Accessibility Summit: http://environmentsforhumans.com

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Usability problem priorities

1. CriticalA problem that will prevent some users from completing a common task

2. SeriousA problem that will slow down some users and force them to find work-arounds

3. Medium A problem that will cause frustration but will not affect task completion

4. Low A quality or cosmetic problem, such as a spelling error, that can damage the credibility of a site.

- David Travis, User Focus

Source: http://www.userfocus.co.uk/articles/prioritise.html

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Both evaluate priorities by impact on the user

How likely is it that this problem will stop someone from being able to use the site?

Priority Label What it covers

Critical Barriers that stop someone from using a site or feature successfully

Serious Problems that cause frustration, slow someone down, or require work-arounds

Annoying(moderate)

Things that are frustrating, but won't stop someone from using the site

Noisy(minor)

Minor issues that might not cause someone a problem, but which damage credibility

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Examples of how usability and accessibility problems interact

These examples are drawn from our experiences doing usability testing. Although we show partial screens from real site, these are simply typical problems, and not unique to those sites.

In most cases, these companies are actively working on both usability and accessibility, and some of the issues described in this presentation have already been fixed.

9Coding errors turn a serious usability problem into a critical accessibility problem

Usability problems (serious)• Too many links (281 of them)]• And 45 lists• 98 Poor headings• Overly complex information

Accessibility barriers (critical)• Missing semantic coding:

• Headings• In page navigation

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Noisy – easy to find - problems masked a critical one

Accessibility (noisy)• Missing alt text• Inconsistent heading coding• Confusing labeling of

sections

But the real problem was

Accessibility (critical)• No way to jump past the

infinite ribbon at the top of the page

11All information and links are “accessible” but rely on visual layout for meaning

Accessibility (serious)• The overall site is

accessible

but • The insert task links

rely on visual position to tell you where the task will be inserted.

Insert Task

Insert Task

12Long pages make information hard to find (even with headers, without a table of contents

Really really long page

Usability & Accessiblity(Annoying to Serious)• On a long page with a lot of

detail, users had trouble finding specific information

Adding a well-designed "on this page" menu helped everyone decide whether this was the right page

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The interface is harder than the test

Usability (serious) Kids have to know how use the tabs

Accessibility (critical)Same problem, but worse because the test question is hidden

No heading

Follows long text

14Participants with disabilities add perspectives to a usability problem

Usability & accessibility(serious)

The general interface is both usable and accessible, but the language and terminology in the content created serious and critical problems for people who did not know university terminology.

15Repeated and inconsistent page titles make the IA incomprehensible

Usability (annoying) Page titles repeat at different levels

Links and titles don't always match

Accessibility (serious)Same problems have more impact for screen reader or zoom text users

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Look at real behavior, not just coding requirements.

People with different interaction styles add depth to usability.

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"The future is already here...it's just not evenly distributed."

– William Gibson

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Whitney Quesenberywhitneyq@centerforcividesign.orgcenterforcivicdesign.org@whitneyq

Jayne Schurickjschurick@knowbility.orgknowbility.org

A Web for Everyoneprint, MOBI, ePUB, printable PDF, DAISYrosenfeldmedia.com/books/a-web-for-everyone/