Identifying Behavioral Strategies of Visually Impaired Users to Improve Access to Web Content

摘要

The World Wide Web is a predominantly visual media for presenting and disseminating information. As such, visually impaired users, who access content through audio interaction, are hindered as the Web is not designed with their needs in mind. To compensate for this, visually impaired users develop behavioral strategies to cope when access to the content becomes challenging. While tools exist to aid visually impaired users in accessing the Web, they tend to focus on adapting content to meet the needs of the device rather than the user. Therefore, to further improve Web access an understanding of the behavioral strategies users employ is required. To achieve this, studies of eleven visually impaired Web users were conducted. The data from these sessions were analyzed to develop a framework for identifying strategies that users may employ when they face difficulties accessing the content. Using data for twenty visually impaired users obtained from an independent study, the framework was validated and shown to be flexible and accurate enough to be applicable to multiple data sources. An analysis of the coping strategies identified from the framework revealed six abstract patterns of coping. These patterns were used as the basis for developing behavior-driven transcoding that transformed static Web documents into interactive content by allowing users to navigate between key elements of the page through a consistent set of key presses. Results obtained from a user evaluation of the transcoding support the use of behavior-driven transcoding as a mechanism for improving access to Web content when compared to existing transcoding techniques. This result allows the coping strategies framework to be used as a foundation for further understanding of the strategies visually impaired users employ on Web sites and the transformations required to allow the Web to be accessible to those users.