This page contains material related to a presentation at the Web Accessibility Best Practices Evaluation Training in Paris, France in July 2004. It is not intended to stand-alone; rather, it is primarily provided as reference material for participants in the training.
Scope of Training and Materials: This one-day training focused on select topics that were particularly suited to the circumstances of this specific hands-on training session. It did not to cover all aspects of evaluating Web accessibility, and did not cover all Web Content Accessibility Guidelines (WCAG) 1.0 checkpoints.
No Endorsement or Recommendation of Evaluation Tools: W3C/WAI does not endorse Web accessibility evaluation tools and does not recommend one tool over another. Some tools were listed, demonstrated, and used in activities in this training. Mention of a specific tool does not imply endorsement nor recommendation. WAI does provide a comprehensive list of Evaluation, Repair, and Transformation Tools for Web Content Accessibility.
Evaluating Web Accessibility
Shawn Lawton Henry, W3C WAI
Last updated: 15 July 2004
Demo: Quick Checks in 5 Minutes
Challenges
- Skilled evaluators
- Limited time & money
Goal-directed Evaluation
- Determine purpose, goals
- Selection
- Thoroughness (preliminary, conformance, comprehensive)
- Reporting
Purpose, Goals of the Evaluation
- Examples
- Encourage improvements in paying client's Web site
- Tool for building awareness
- Tool for teaching accessible techniques
- Management needs to know status
- Third-party conformance report for government benchmarking
- Single engagement, initial report, ongoing engagement
- Other...
1. Selection
- Templates
- that impact all or many of your web pages
- Style sheets
- that impact all or many of your web pages
- Home page
- that is often the first impression
- Most important pages
- (and the path to get there)
- Frequently-used, high traffic pages
- (and the path to get there)
- Different types of pages
- One of each feature or functionality (for example, data table, form)
- One from each developer or development group
- Depending on situation
- Pages and applications soon to be re-designed or re-coded
- Projects in development
- Prototypes not yet released
Discussion
- How long does it take to evaluate a page?
Tips: Comprehensive Evaluation
- Usability testing with participants with disabilities
- Caution: Carefully consider feedback
- Resource: Accessibility in the User-Centered Design Process (not from W3C WAI)
- Screening Techniques
- Activity: various screening techniques
- Video: participant using screen magnification software
Tip: Determine which features/functionality applicable
- For example,
- Image maps
- Data tables
- Layout tables
- Frames
- Applets and scripts
- Multimedia
- Forms
Example Evaluation Situations and Parameters
| Example |
Awareness, Outreach |
Consultant |
On-going Monitoring |
Planning, Training |
Benchmarking |
| Situation |
Encourage accessibility improvement |
Usability and accessibility consultant |
Existing accessible site |
|
Third-party conformance report for government benchmarking |
| Goal |
Highlight major accessibility problems |
Demonstrate excellence |
Confirm no new problems |
Determine main issues |
Data covering many sites |
| Page selection |
Important pages (to organization) |
All Web pages (small site) |
Spot checks, tool checks |
Samples pages, early prototypes |
(challenging)
|
| Thoroughness |
Preliminary |
Comprehensive |
Conformance |
Preliminary |
Probably select conformance |
| Reporting |
Encouraging, educating, referring |
Short, informal |
Minimal, informal |
- Executive summary
- Plan of action
- Details, examples, references
|
Data |
Evaluation Throughout Development
| When/What |
Why |
| Requirements |
ensure that accessibility is included |
| Wireframes |
know what to watch for in development |
| Visual/graphic design |
things like color contrast |
| Early low- or medium-fidelity prototype/templates |
catch issues early, while there's time to make changes |
| Final prototype/templates, before replication |
catch all the details - don't want them propagated |
| Complete pages, QA |
check things that changed, make sure nothing slipped by |
Evaluation Tools
Types of Tools
- Web Accessibility Evaluation
- Test against accessibility rules
- Web Accessibility Repair Tools
- Facilitate correcting problems
- Transformation Tools
- Modify presentation to highlight issues
- Validation
- Test against markup rules
Features
- Reveals markup
- Provides explanations
- Allows customization
- Test parameters
- for example, skip certain checkpoints
- Report details and format
- For developers, evaluators, managers, etc.
Tool Cautions
- None are “it”
- Avoid approving or condemning site because of tool report
- Avoid coding just to make a tool happy
Evaluation Tools Need People
- Spell check analogy
- "tool"- instrument used by a craftsman or laborer at his work (Webster)
- False positives and false negatives
- The bottom line:
Tool can identify potential errors, knowledgeable human must assess
Resource: Web Accessibility Evaluation Tools Need People (not from W3C WAI)
Tool Tour
Activity
- Bobby or other online tool
- Your pages
- Page you think will do well
- Page you think will do poorly
- Home Page Reader
- To stop reading: [Esc]
- To start reading: [space bar]