The Dyslexic User's Interface Support Tool (DUIST) : a framework for performance enhancing interface adaptation strategies for dyslexic computer users

Due to the nature of the symptoms experienced by dyslexic individuals (e.g. defective visual processing, short term memory deficit and motor control problems) an investigation into support strategies to aid persons suffering from the condition seems strongly justifiable. As such, an extensive review of existing support techniques for dyslexic computer users are explored leading to the formulation of four central research models; dyslexia symptoms, symptom alleviating interface strategies, adjustable interface components and a dynamically adaptable interface preference elicitation mechanism. These models provide the foundation for the design of the Dyslexic User’s Interface Support Tool (DUIST) framework. Using a user centred design approach, the support framework is developed, tested and subsequently evaluated with positive results. Performance gains for dyslexic subjects in reading speed and reading accuracy exemplify the apparent benefits of framework utilisation (e.g. dyslexic mean reading speed increased by 4.98 wpm vs. control gains of 0.18 wpm; dyslexic mean reading errors reduced by 0.64 per 100 words vs. control reductions of 0.06 fewer errors per 100 words). Subsequent research into the long-term impact of framework utilisation; the perceived benefits of applying research formulated models to interfaces designed for dyslexics; and alternative strategies to portability all now seem justified. That said, the findings presented thus far warrants investigation by any reader actively interested in dyslexia; strategies for dyslexia symptom relief support environments for dyslexic computer users; applications of adaptive interfaces; and all potential system designers who may be considering developing any type of graphical interface for a dyslexic user group

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