Usability vs. Accessibility

Usability and Accessibility Considerations - User Experience for SeniorsAccessibility is the extent to which the content and functionality of a technology product is available to the widest possible audience.  It is a “best practice” when designing a user experience for seniors, but is also required by law in some circumstances, particularly with reference to people with disabilities.  Usability on the other hand, is a measure of how easy it is to successfully use a product.  It is rarely required by law, but it is always something to strive for.  A user interface can be accessible but not usable, or vice versa.  The goal of user interface designers should be to make products both accessible and usable.

It should be no surprise that the usability needs of seniors often overlap the accessibility needs of persons with disabilities.  The World Wide Web Consortium (W3C) Web Accessibility Initiative AGE (WAI/AGE) project found that many of the guidelines for making web sites accessible to people with disabilities match the requirements of those for older people.  The study also found that usability improvements that help older adults also help people with disabilities.  In fact, the WAI/AGE project concluded that “designing websites for seniors is largely just good design”.  In other words, designing a product which provides a good user experience for seniors can enhance its usability for all age groups.  W3C then folded their WAI/AGE specific recommendations into their broader web content accessibility guidelines.

W3C’s Web Content Accessibility Guidelines (WCAG) 2.0 cover a wide range of recommendations for making web content more accessible.  Following these guidelines will make content available to a wider range of people with disabilities, including vision impairments, deafness and hearing loss, learning disabilities, cognitive limitations, limited movement, speech disabilities, photosensitivity and combinations of these.  While designed for websites, WCAG 2.0 success criteria are largely written as testable statements that are not technology-specific.  Hence to a very large extent they apply to all types of user interfaces.  Many of the mitigation strategies provided herein are based on WCAG 2.0.

Accessibility checkers and validation tools which also can be used to test designs for seniors:

  • Google: Android Accessibility Scanner – Tool that suggests accessibility improvements for Android apps without requiring technical skills. Accessibility Scanner suggests improvements such as enlarging small touch targets, increasing contrast, and providing content descriptions.
  • University of Toronto: A-Checker – Used to evaluate HTML content for accessibility problems by entering the location of a web page, uploading an html file, or by pasting the complete HTML source code from a Web page.
  • Accessibility Check – Evaluates your page against a subset of the WAI guidelines. These guidelines form the basis for most global legislation relating to accessibility and user experience for seniors.
  • Site Valet – Comprehensive QA system for Web-based technologies. It features a new GUI Client, improved accessibility analysis with full audit trail, and comprehensive XML support.
  • University of Illinois at Urbana-Champaign: Functional Accessibility Evaluator – Evaluates a website or a single web page based on the W3C Web Content Accessibility Guidelines (WCAG) 2.0 Level A and AA requirements. This is a valuable tool for designing a good user experience for seniors.
  • HERA – A tool to check the accessibility of Web pages according to the specification Web Content Accessibility Guidelines (WCAG) 1.0. HERA performs a preliminary set of tests on the page and identifies any automatically detectable errors or checkpoints met, and which checkpoints need further manual verification.
  • Fraunhofer Institute for Applied Information Technology: ImergoA complete web compliance suite targeted to improve the quality of web applications by providing a flexible testing framework that can address a wide variety of requirements, such as markup validation, web accessibility, search engine optimization (SEO), mobile web, performance restrictions, corporate identity, etc.
  • Da Silva Online Website Evaluator – A Portuguese language website tool for checking compliance with W3C’s Web Content Accessibility Guidelines (WCAG) 2.0.
  • Universidad Carlos III De Madrid: Web Accessibility Evaluator (WAEX) – A website tool for checking compliance with W3C’s Web Content Accessibility Guidelines and Mobile OK Basic Tests.
  • Web Accessibility Evaluation Tool (WAVE)A tool to help web developers make their web content more accessible.  WAVE has many tests for true accessibility, including many checks for compliance issues found in the US GSA Section 508 and WCAG 2.0 guidelines.  It is also available as an API.

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