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Accessible Dynamic QTI-Questions


Jens Voegler


Gerhard Weber



Abstrakt

 

1 Preamble
Learning Management Systems (LMS) are used for supporting teaching in schools and universities and are getting more important. These LMS offer many advantages for lear- ners and teachers. Learners can access teaching material time- and location-independent. Afterwards they can test their learning success. Therefor the LMS supports different kind of answer-techniques, e.g. single and multiple choice, ordering elements by Drag’n’Drop. Some of these technique use visual interaction like Drag’n’Drop and pairing elements which may cause barriers for users with special needs.
In addition the teachers will be relieved. There exist some editors for creating tests and the LMS checks the completed tests and evaluates the answers automatically. Different standards and programs exist for creating online tests. Current standards for the description of content of learning are Sharable Content Object Reference Model (SCORM) and IMS Question & Test Interoperability (QTI). Besides commercial systems also OpenSource-LMS are available. Their accessbility and usability is important when selecting a LMS. This has considerable impact for impaired and non-impaired users.
 
2 LMS
In which way a LMS is used depends on the teacher. A study of the Saxonian Online Platform for academical Teaching and Learning (OPAL) 1 shows that most often used activity was downloading content like lectures and excerises. For improving the usage of collaborative functions like bulletin board, shared calendars and online tests our team had evaluated this system with visual impaired persons and worked together with the provider for the realization of our recommendations in later updates. Our team is also running a LMS called Moodle2 . The advantages of Moodle are:
  • OpenSource
  • tested with visual impaired and blind users (see (PRESCHER])
  • modified for enhancing the accessibility
  • blind and visual impaired students use our LMS
We offer our students3 tests for their exam preparation and bulletin boards for news, discussions and questions. Both, online tests and bulletin boards are used during the terms and for testing the knowledge of different topics.
 
2.1 QTI
QTI is a standard format for the representation of assessment content and results. QTI offers different interactions for answering a question (see IMS Global Learning Consortium). These interactions are single-Choice and Multiple-Choice (simple), input fields (textbased) and Drag’n’Drop or order/sort elements (graphical).
The QTI standard supports additional information like description of pictures in its specification. Furthermore there is no definition in which way the assessment content will be rendered and presented to its user. But often HTML and JavaScript is used for this. And this is the main problem, because the interactive responses are not accessible for assistive technologies.
 
2.2 Accessible interactive Responses
Different studies show that interactive response can be accessible, if they fulfill current guidelines and specification like Web Content Accessibility Guideline 2.0 (WCAG 2.0), Web Accessibility Initiative - Accessible Rich Internet Applications (WAI-ARIA) and HTML5. Responses like Drag’n’Drop and sort elements can be accessible. Therefore just HTML5, ARIA, CSS and JavaScript is required.
In our current project it is the main goal to enhance the accessibility of such interactive response. Based on QTI, HTML5, CSS and WAI-ARIA different kind of interactions are developed and tested with blind and visually impaired users. Blind users were asked what kind of interaction they prefer when asked to sort a list of multiple items. The result are two kind of interaction: select’n’move and select’n’paste. Select’n’move is performed by
selecting/grabbing an element and moving it via the arrows keys. Select’n’paste after is performed by selecting an element and moving the focus. With second selection the selected element is pasted at the focussed position. Both techniques were tested with blind users successfully.
Another concept of accessible Drag’n’Drop is using a popup menu for selecting the drop target (see [HEIMER]). In the same way the users can adjust the ordering of the dropped elements by select’n’move or select’n’paste. Additional information about the visual changes after moving/pasting a element will present in an hidden live-region. We modify an existing QTI-Player by adding these accessible features and make the interactions accessible for assistive technologies.
 
3 Conslusion
By using technologies like HTML5, CSS and JavaScript dynamic web pages and particular Drag’n’Drop accessible for assistive technology. All three proposed accessible interaction techniques are subject to preferences of an individual user.
 
References
Books
HEIMER, Andrea. Usability assistiver Technologien in dynamischen Webinhalten, 2011. Diplomarbeit, TU Dresden; Dresden.
 
PRESCHER, Denise. Nichtvisuelle Benutzungsoberfl¨chen im E-Learning, 2008. Großer a Beleg, TU Dresden; Dresden.
 
Electronic articles
IMS Global Learning Consortium. IMS Question and Test Interoperability Assessment Test, Section, and Item Information Model. Available in
URL http://www.imsglobal.org/specifications.html
 

1more information https://bildungsportal.sachsen.de/opal/dmz/
2https://moodle.org/
3A pilot study has shown that mouse-based quizz techniques as described above can be mastered by
blind students. Results will be reported in the full paper.

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