The impact of accessibility assessment in macro scale universal usability studies of the web

This paper presents a modelling framework, Web Interaction Environments, to express the synergies and differences of audiences, in order to study universal usability of the Web. Based on this framework, we have expressed the implicit model of WCAG and developed an experimental study to assess the Web accessibility quality of Wikipedia at a macro scale. This has resulted on finding out that template mecha-nisms such as those provided by Wikipedia lower the burden of producing accessible contents, but provide no guarantee that hyperlinking to external websites maintain accessibil-ity quality. We discuss the black-boxed nature of guidelines such as WCAG and how formalising audiences helps leverag-ing universal usability studies of the Web at macro scales