Pros and Cons of Web Accessibility Evaluation and Repair Tools
Terry Thompson
AccessIT, University of Washington
tft@u.washington.edu
http://www.washington.edu/accessit
What this presentation is not
- A review or comparison of specific products
What this presentation is
- A look at the role software can play in an organization's web accessibility
plan
What software is available?
An extensive list maintained by the W3C
http://www.w3.org/WAI/ER/existingtools.html
A Wide Range of Software
- Manual evaluation tools
- On-line accessibility assessment tools
- Desktop software
- Evaluation vs. Repair
- Server/Enterprise Solutions
A few of the best known vendors:
Free Tools
Open Source Project
Planning for web accessibility
- Identify a point person
- Empower the infrastructure
- Develop a web accessibility plan, including priorities, responsible parties,
and deadlines
- Integrate accessibility into web design trainings for instructors and staff
- Establish web accessibility policies &/or guidelines (at any level, institutional
to individual)
- Provide accessibility support
- Consider supplementing your efforts with web accessibility evaluation & repair
software
How can software help?
- Spot problems you might have missed in a manual inspection
- Sitewide
benchmark
- Tool for educating web developers using their own web pages
Shortcomings of software
- Many aspects of web accessibility are subjective (only X% can be automatically
assessed)
- False positives, false
negatives
- For educational role, many products present overwhelming amounts
of information in their reports (confusing)
Is the software effective
“A study of automated web site evaluation tools”
Melody Ivory, Aline Chevalier
http://scholar.google.com/url?sa=U&q=ftp://ftp.cs.washington.edu/tr/2002/10/UW-CSE-02-10-01.pdf
Study Design
9 experienced web designers are asked to modify 5 websites, and given 20
minutes for sites 1-5, 40 minutes for site 5:
- Manually, using no automated tool
- Using Watchfire Bobby
- Using W3C HTML Validator
- Using Usablenet LIFT
- Using all of the above
Study Results
- Automated tools revealed more problems than designers found manually
- There were no significant differences in the number of problems that were
corrected using automated tools vs. manual method
W3C Evaluation And Report Language (EARL)
The Evaluation and Report Language (EARL) is a general-purpose language for expressing test results. Web accessibility evaluation tools can use this language as a standard to express evaluations results in a platform independent format. Web authoring tools and other applications could aggregate these results from different tools to combine manual and automatic testing in an efficient way.
http://www.w3.org/WAI/intro/earl.php
How to choose a product
See AccessIT Knowledge Base article How can I select a web accessibility software tool?
http://www.washington.edu/accessit/articles?244
Choose those questions that are relevant to your needs, and explore them with
vendors:
- What operating systems are supported?
- Which sets of accessibility checkpoints are predefined?
- Is the tool able to automate repairs?
- Is the user interface accessible and usable?
- Does the tool assess site quality issues beyond accessibility?
- Does the tool check spelling?
- Does the tool include page preview filters?
- Can the product spider or crawl an entire website or domain?
- Can the tool follow non-HTML links?
- Can the tool assess the accessibility of any non-HTML content?
- How does the tool handle potential obstacles such as passwords, cookies,
required form fields, and session IDs?
- Does the tool have built-in features to facilitate web accessibility project
management?
- How are the results presented?
- Is the results data exportable?
- Can the tool be run from a command prompt or as part of a batch process?
- Is the tool available with a software development kit (SDK) or open application
program interface (API)?
- How much does the tool cost?
What about Usablenet LIFT Text Transcoder?