Designing electronic graphic symbol-based AAC systems : a scoping review

Abstract

Background: Electronic graphic symbol-based augmentative and alternative communication (AAC) systems can facilitate participation and engagement in various life activities by providing individuals with complex communication needs access to alternative forms of communication. However, designing such systems can be a daunting and complex task. Not only do the designers have to keep up with the ever-growing advances in technology, but they must also try to match the varying features available for graphic symbol-based AAC systems with the heterogenous group of individuals for whom these systems are designed, the tasks that the system should help the users to accomplish, and the context of use. Moreover, the interchangeable use of Human Centred Design (HCD) terminology, and the eclectic approach to designing assistive technology, makes identifying and using a particular design approach and method to design graphic symbol-based AAC systems difficult. Therefore, the aim of this study is to map the literature reporting on the design studies of such systems and to provide an overview of documented approaches, principles, input, outcomes, and methods used in the design of graphic symbol-based AAC systems to facilitate an understanding of the current state of the field. Methods: A scoping review was conducted whereby a comprehensive and multifaceted search of 11 databases found 28 studies that met the predetermined selection criteria. Descriptive data was extracted independently by two persons, using a predetermined data extraction table. Data was extracted relating to seven areas of interest, namely (a) the characteristics of the design studies, (b) the features of the systems designed, (c) the design approaches and principles used, (d) the input obtained before and during the design process, (e) persons involved, (f) product evaluations and outcomes, and (g) the limitations and recommendations provided within these studies. Data was analysed using descriptive statistics (predominantly frequency counts) and summarised in text and using graphs. Results: The findings indicated that most of the studies reported on the design of graphic symbol-based AAC applications or software to be loaded onto mobile technology devices, which is in accordance with the mobile technology revolution. HCD approaches were rarely and inconsistently reported, and few studies followed all six HCD principles. A positive outcome was the inclusion of users/stakeholders within the design process; however, due to varying constraints within the design process, the type of and extent to which they were included varied. The methods used to gain information and evaluate the product are consistent with the literature. Few of the systems designed are currently available to the public and ongoing development is required. Conclusions: There is a need for designers to be more transparent about the type of design approach used to guide the system design and also to clearly report on design approaches and processes used. Research is required to explore further the development of graphic symbol-based AAC systems and to obtain a better understanding of the decision-making throughout the design process.