Page 205 - THE DUTCH TALKING TOUCH SCREEN QUESTIONNAIRE

input has had a great impact on the design of the TTSQ and resulted in the guidelines for designing interactive questionnaires for persons with low literacy which are presented in Chapter 3 of the current thesis. Because of the input of these designers, the screen of the TTSQ, for instance, contains as few functions and buttons as possible, and does not have a back function. Instructions and background information are only given in spoken, not in written, text. All pictures and illustrations shown on the screens are as concrete as possible, functional and relevant to the question that is being asked. Respondents are provided with regular overviews of given answers and a Stop function which gives them the command to stop completing the questionnaire at any time. Furthermore, the TTSQ contains answer options in the form of buttons with text, a body chart, pictures on which activities are shown, and a numeric rating scale. The numeric rating scale is colored from green for ‘not severe’ to red for ‘severe’ and contains absolute figures as opposed to an ongoing scale like, for instance, a Visual Analogue Scale. Everything in the design of the TTSQ is aimed at keeping the operation of the TTSQ simple, avoiding information overload and helping respondents to oversee their tasks, without feeling pressured into doing something they fear they cannot do. The screen samples of Hahn et al. in fig. 5.2, 5.3 and 5.4 [15,17,19] show a lot of buttons and answer options which contain text in a small font, instructions in written text accompanied by an illustration which is not functional or relevant in relation to the written text, and a screen which contains a complicated question, accompanied by a functional picture. One could argue about whether or not the images/pictures used in fig. 5.2, 5.3 and 5.4 are concrete enough for people with low literacy to help them understand the question better. Looking at the designer guidelines in Chapter 3 of this thesis, the screens in fig. 5.2, 5.3 and 5.4 may not be the calm and clear images low literacy respondents are looking for. This may be even more true for the screen of Thumboo et al. in fig. 5.5 [25], which contains a lot of information and functions in various forms. Which kinds of screens, features or functions do and do not contribute to the ease of use of the various kinds of TTs is hard to say, though. The results of all earlier published studies on TTs [15-26] are difficult to compare with the usability results for the Dutch and Turkish versions of the TTSQ, presented in Chapter 4.2 and 4.3 of this thesis, because of differences in methodologies used and study set- ups.
General discussion
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