This is the first of two papers summarising studies reporting on the design of electronic graphic symbol-based augmentative and alternative communication (AAC) systems, in order to determine the state of the field. The aim of this paper was to provide an overview of the general characteristics of the studies and to describe the features of the systems designed.Methods: A scoping review was conducted. A multifaceted search resulted in the identification of 28 studies meeting the selection criteria. Data was extracted relating to four areas of interest, namely (1) the general characteristics of the studies, (2) features of the systems designed, (3) availability of the systems to the public, and (4) the design processes followed. In this paper, findings relating to the first three areas are presented.Results: Most study authors were affiliated to fields of engineering and/or computer science and came from high-income countries. Most studies reported the design of AAC applications loaded onto mobile technology devices. Common system features included customisable vocabulary items, the inclusion of graphic symbols from both established AAC libraries and other sources, a dynamic grid display, and the inclusion of digital and/or synthetic speech output. Few systems were available to the public. Conclusions:Limited justifications for many of the complex design decisions were provided in the studies, possibly due to limited involvement of rehabilitation professionals during the design process. Furthermore, few studies reported on the design of graphic symbol-based AAC systems specifically for middle-and low-income contexts and also for multilingual populations.

Purpose: This is the second of two papers summarising studies reporting on the design of electronic graphic symbol-based augmentative and alternative communication (AAC) systems. The aim of this paper was to describe the design approaches used, and to determine to what extent the principles of human-centred design (HCD) were reflected in the design approaches and processes used.Methods: A scoping review was conducted. A multifaceted search resulted in the identification of 28 studies meeting the selection criteria. Data was extracted relating to four areas of interest, namely (1) the general characteristics of the studies, (2) features of the systems designed, (3) availability of the systems to the public, and (4) the design processes followed. In this paper, findings related to the last area are presented.Results: Design approaches were often inconsistently described. User-centred design was mentioned more often than HCD. Even so, various HCD principles were considered in most studies. Notably, stakeholders were involved in the design process in all studies. However, users were not involved in all studies and stakeholder roles were predominantly informative rather than collaborative. Prototype and product evaluations focused mostly on usability rather than user experience. Although many design teams were multidisciplinary, engineers and computer scientists predominated. 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. The application of HCD to the design of graphic symbol-based AAC systems is still limited.