Web Accessibility

A Combined Agile Methodology for the Evaluation of Web Accessibility

Firas Masri, Sergio Luján-Mora. A Combined Agile Methodology for the Evaluation of Web Accessibility. IADIS International Conference Interfaces and Human Computer Interaction 2011 (IHCI 2011), p. 423-428, Rome (Italy), July 24-26 2011. ISBN: 978-972-8939-52-6.

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To assure and certify the fulfillment of web accessibility guidelines (WCAG 1.0 & 2.0) and to guarantee accessibility to all disabled users, various accessibility evaluation methods have been proposed, basically classified in two types: qualitative methods (analytical and empirical) and quantitative methods (metric-based methods). As no method by itself is enough to guarantee full accessibility, many studies advice to combine these methods between each other in order to guarantee better results. Some recent studies present combined evaluation methods between qualitative methods only, thus leaving behind the great power of metrics that guarantee objective results and task diversity. To achieve this goal, the current paper proposes a systematic combined agile accessibility evaluation method based both on qualitative and quantitative evaluation methods. This proposal presents an evaluation methodology that combines between the essential analytical evaluation methods and the empirical user test methods. Finally, WAB metric (Web Accessibility Barrier) is included to summarize objectively the final results and amplify the use of this method to cover all types of evaluations tasks, like validating, certifying and comparing processes.

Keywords: Web accessibility, Empirical evaluation methodology, User test.


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