Evaluation Approaches for Specific Contexts
Page Contents
Introduction
This document supplements the documents Preliminary Review of Web Sites for Accessibility and Conformance Evaluation of Web Sites for Accessibility. It describes considerations for evaluation of large and complex Web sites, during the development process, ongoing monitoring, evaluation of legacy sites, and evaluation of dynamically generated Web pages.
Evaluation during the development process
Evaluation during the development process is essential. It can sometimes be difficult, as both in-house and subcontracted Web developers sometimes prefer to establish the site design and demonstrate their progress before getting feedback. However, accessibility issues identified early are easier to correct and avoid. Effective evaluation during the design period can include:
- Establishing clear requirements for the expected accessibility conformance level.
- Involvement in initial planning meetings for the site.
- Agreeing on a review schedule during the development process.
- Providing information on evaluation approaches so that the developers can at least do preliminary reviews on their own.
Ongoing monitoring
To maximize likelihood that a Web site will maintain a given conformance level in the future, the following provisions should be in place:
- Clear statement of expected conformance level and scope of Web site it applies to.
- Clearly identified individuals responsible for monitoring the site, and follow-up procedures they can use to rapidly bring non-conformant pages into conformance.
- Clear expectations with regard to frequency, method, and scope of evaluations.
- Processes for validating and evaluating all changed pages and new types of pages before they are added to the site.
- Software to facilitate evaluation.
- Incorporation in Web site of address for feedback on accessibility of site.
- Automated or semi-automated tests to identify problems identified in the comprehensive evaluation.
Note: A full conformance evaluation is not necessarily required at each milestone in an ongoing review process. Steps like repeated user testing may only be required after major template or content changes.
Evaluation of legacy sites
Occasionally Web sites that are "frozen" (legacy; no longer actively maintained) are found to have substantial accessibility problems. It can be difficult to determine how to address these. It is helpful to:
- identify who the current owner is;
- determine whether they have any obligation or interest in making the site accessible;
- after evaluating the site, outline for the owner the changes that would be required to retrofit the site for accessibility;
- identify and propose resources and a timeline for retrofitting the site;
- disclose, publicly, accessibility problems on the site.
Evaluation of dynamically generated Web pages
Dynamically generated pages are usually assembled from one or more templates that provide common layout and navigation features, and content provided automatically from a database or other content management system. To achieve full conformance the accessibility of both templates and generated content must be evaluated. It is not sufficient to evaluate only templates: content may also contain markup, or be required to contain markup in order to be accessible. The following are things to consider:
Templates
Evaluate all templates as follows:
- Evaluate static templates using the Web Content Accessibility Guidelines 1.0.
- Add a minimal amount of plain text content to the templates and evaluate again.
Note: if templates are generated by authoring software evaluate the capability of the authoring tool to include accessible features (see Authoring Tools Accessibility Guidelines Overview), for example:
- Does the generated tab order from the template allow getting to the generated text content effectively?
Content
Evaluate the capability of the content management system to store and generate accessibility information (see Authoring Tools Accessibility Guidelines Overview). Consider the following questions:
- Are images supplied with
alt
texts, and if needed, thelongdesc
? - Do generated data tables have accessibility aids (for example: captions,
id
onth
header cells, etc.)? - If generated video, is it captioned?
- If generated audio narrative, is textual equivalent available?
- Is the generated markup valid?
Templates and content combined
For pages that are generated as a result of a query to a database, the source generated as the page is rendered should be captured and evaluated using the Web Content Accessibility Guidelines 1.0 -- [may require operator intervention]. Note: if all dynamic content cannot be evaluated, generate broadly representative samples, capture content, and test the output. Do the generated pages retain the accessibility features evaluated under templates and content when combined?
Related pages
This document is part of a multi-page Evaluating Web Accessibility resource suite that outlines different approaches for evaluating Web accessibility.