Research Report on Web Accessibility Metrics – W3C Working Draft 30 August 2012
Americas, August 31 2012
Web accessibility metrics are an invaluable tool for researchers, developers, governmental agencies and end users. Accessibility metrics help indicate the accessibility level of websites, including the accessibility level of individual websites, or even large-scale surveys of the accessibility of many websites. Recently, a plethora of metrics has been released to complement the A, AA, and AAA Levels measurement used by the WAI guidelines. However, the validity and reliability of most of these metrics are unknown and those making use of them are taking the risk of using inappropriate metrics. In order to address these concerns, this note provides a framework that considers validity, reliability, sensitivity, adequacy and complexity as the main qualities that a metric should have.
A symposium was organized to observe how current practices are addressing such qualities. We found that metrics addressing validity issues are scarce although some efforts can be perceived as far as inter-tool reliability is concerned. This is something that the research community should be aware of, as we might be making efforts by using metrics whose validity and reliability are unknown. The research realm is perhaps not mature enough or we do not have the right methods and tools. We therefore try to shed some light on the possible paths that could be taken so that we can reach a maturity point.
For more information, visit http://www.w3.org/TR/accessibility-metrics-report/