UIAAC: A Method for Designing of Graphical User Interface for
Augmentative and Alternative Communication
William Sanchez
, Christian Collaguazo
, Daniela Prado
and Priscila Cedillo
Computer Science Department, University of Cuenca, Ecuador
Keywords: Graphical Interface, Older Adults, Accessibility, Pictograms, AAC, Design, Software Engineering,
Health Care.
Abstract: The world's population is aging, which is reflected in the increased proportion of older adults, both in
developed and developing countries. In 2019, 1 in 11 people exceeded 65 years old; and it is projected that
by 2050, this proportion will be 1 in 6 people. Among the most common problems older adults face are those
linked to physical, auditory, and visual impairment and, affect, the way they communicate and interact with
others. While the usual way of communication is through speech, 1.3% do not depend on verbal language,
and as a result, their communication needs are not met. Therefore, it is necessary to search for other modes of
communication (apart from speech), which are used to express thoughts, needs, desires, and ideas. An option
is Augmentative and Alternative Communication (AAC), which presents methods and technology to help
people develop or regain communication ability. Thus, this document presents a method called UIAAC, which
aims to facilitate the design of graphical user interfaces for AAC systems oriented to older adults and
incorporate pictograms as a means of communication. The presented method is aligned with usability
standards and considerations of experts in AAC, gerontology, software quality engineers, and user-centered
design. To assess the feasibility of the method, the design of a prototype interface and a case study that
assesses the perception of the prototype's use is presented. The evaluation was developed from the point of
view of the psychological area and the end-user (older adult).
Currently, the proportion of older adults has increased
considerably in the world (Office Statistics, 2015).
This age group faces many problems related to their
age; the most common are physical, hearing, and
visual impairment that significantly affects how they
communicate and interact with other people (World
Health Organization, 2011). For this reason,
researchers are motivated to seek alternative
technologies or methods to help people improve or
regain the ability to communicate. Thus
Augmentative and Alternative Communication
(AAC) appears and becomes indispensable
(Beukelman & Light, 2020). It can be achieved
through AAC systems, which are applications that
incorporate some technological means as information
output and provide innovative solutions for a wide
range of users with speech disabilities (Waller, 2019).
One of the means of interaction that the AAC
incorporates is the use of pictograms, which are
figurative drawings, used to transmit information
directly, indicate an object, verb, place, or express an
idea when users speak with limited language skills or
have visual problems (Tijus et al., 2007). The receiver
can interpret pictograms in a more precise and agile
way than words. Therefore they serve as an instant
reminder, such as a danger sign or a specific message
(Portugal et al., 2013).
Most AAC systems incorporate a graphical
interface for user interaction. This interface must
consider the criteria of usability and accessibility to
provide the best possible user experience; if an
interface is adequate, the user will be able to slide and
Sanchez, W. and Prado, D.
UIAAC: A Method for Designing of Graphical User Interface for Augmentative and Alternative Communication.
DOI: 10.5220/0010527602560264
In Proceedings of the 7th International Conference on Information and Communication Technologies for Ageing Well and e-Health (ICT4AWE 2021), pages 256-264
ISBN: 978-989-758-506-7
2021 by SCITEPRESS Science and Technology Publications, Lda. All rights reserved
use the system without making much effort. On the
contrary, the user can easily become confused,
resulting in low interaction efficiency (Pressman,
Consequently, the design and construction of
interfaces are an essential part of the software
development process, and in most cases, they account
for about half of the code developed in a system
(Labib et al., 2009). Several primary studies address
the creation of AAC systems and graphical interface
design oriented to end-users in different domains. In
this sense, Keskinen et al. (2012) present a
communication system called SymbolChat, which
considers the needs of users from different
perspectives by customizing the elements of the
graphical interface displayed to the user. Although
this system presents a good alternative for
communication, it does not focus on older adults and
does not consider accessibility aspects aimed at this
particular group. Miguel et al. (2018) present a
project that focuses on designing graphical interfaces
aimed at older adults called Ni nanna, which consists
of a web application for touch devices that provides
advice from older adults with knowledge in artistic
activities to users who require some advice. Its
interfaces are designed according to the User-
Centered Design (UCD) methodology that proposes a
design based on understanding, study, design,
construction, and evaluation. The present research
does not specify details of the process followed in
each subphases. These proposals address the design
of interfaces and forms of interaction; however, the
users' skills to whom they are directed are not
directed, which represents difficulties at the time of
their use (Al Mahmud & Martens, 2016). In general,
this leads to not effectively measuring the usability of
the different components presented to the user
(Saturno et al., 2015).
Consequently, it is necessary to have a method
that guides user interface design with AAC
communication modalities, to improve the interaction
between older adults and high-tech AAC systems
through pictograms. This document presents a
method to design graphical interfaces for the AAC
using pictograms. It has been named UIAAC (User
Interface Alternative and Augmentative
Communication). This method includes all aspects
related to accessibility in order to design effective
interfaces for older adults. Therefore, the main
contributions of this research are: i) An initial version
of the IUAAC method, its phases, guidelines, and
artifacts involved, ii) the design of a functional
prototype of an interface for an AAC system,
designed taking into account each step of IUAAC, iii)
a case study that shows the use of the prototype aimed
at improving cognitive abilities and that has been
used by two older adults, their perceptions and
comments on the experience of using the prototype,
and iv) the psychologist's point of view on the
designed prototype.
Finally, this article has the following structure:
Section 2 presents the related works; Section 3
presents the IUAAC method and its phases; Section 4
shows the feasibility of the method by designing an
interface for an AAC system; section 5 presents a case
study in which older adults and health experts
participate; and finally, Section 6 presents the
conclusions and future work.
This section presents studies that present methods or
considerations for designing and implementing
interfaces for AAC systems. The objective is to verify
the existence of methods to design or build interfaces
for AAC systems that use pictograms and are aimed at
older adults. Miguel et al. (2018) present an interface
to facilitate the interaction of the older persons with
people who require some advice, for which they use
the UCD methodology. Griffith et al. (2014) present a
study in which they examine how an AAC device's
interface design influences people's behaviors with
aphasia during a narrative counting task. Likewise,
Walsh (2010) presents the design and development of
an intuitive interface for an AAC system that is based
on commercial quality statements.
On the other hand, Pavlov et al., (2018) present a
study that describes the approach and decisions that
should be considered to build accessible interfaces for
users with verbal and written communication
disorders. Furthermore, it describes the TESI system's
interface design, whose objective is to improve oral
expression skills. Finally, Light et al. (2019) present
research on the impact of the AAC variables in
children and adults' visual attention with acquired
diseases; it also presents considerations on these
variables' implications for effective design of the
interfaces for visual scene displays.
Moreover, older adults are immersed in a society
that experiences a constant advance in information
and communication technologies (ICT) (Agudo
Prado et al., 2013). It has been determined that ICT
support in the AAC has been recognized as a key
factor to improve the inclusion of people with
complex communication needs in daily life. It is
supported by Matijević et al. (2014), who present
a method of initial automatic adaptation of user
UIAAC: A Method for Designing of Graphical User Interface for Augmentative and Alternative Communication
Figure 1: Main method for design of graphical user interface to AAC systems (UIAAC).
interfaces, which is then distributed among AAC
applications through a specialized platform. This
solution's goal is to produce components without the
need for actual user testing. According to the
solutions presented, it is possible to conclude that
there is no method for designing interfaces for AAC
systems where pictograms are used to communicate
aimed at the older persons. This conclusion is
supported by a systematic review that we have carried
out previously and which is expected to be published
soon; It has the objective of knowing which are the
existing methods, tools and technological solutions
used in the design of AAC interfaces and creation of
AAC solutions in general.
Therefore, for the design of an interface for an AAC
system, aimed at improving the communication skills
of an older adult, a design method has been created,
which considers accessibility characteristics and also
integrates several professionals from different areas
of knowledge (e.g., psychologists, software
engineers, project specialists).
The first activities concerning to UCD are alinged
with the principles proposed by Gould & Lewis
(1983); here, some activities oriented to interface
design have emerged, for example, those proposed by
Wallach & Scholz (2012).
The UIAAC method contains the following
phases: i) scope, ii) analysis, iii) prototype design, iv)
prototype evaluation, and v) implementation. These
phases are presented in Figure 1, and each of them is
explained below:
3.1.1 Scope
This activity is shown in Figure 1 (1), where the AAC
domain expert, the project manager, and the
gerontology specialist intervene. Understanding the
domain and shared knowledge among the participants
makes it possible to obtain the following artifacts:
user needs and problems, scene definition, user
profile, and project structure. They serve as the basis
for the analysis phase. In these documents, the
scenario where the user will interact with the system
will be detailed. A user profile will also be obtained
with different characteristics to understand better the
problems and needs that the user presents and, finally,
a project structure to guide each phase of the proposed
3.1.2 Analysis
This activity is shown in Figure 1 (2). It is based on the
user needs and problems, scene definition, user profile,
and project structure documents. The domain expert,
ICT4AWE 2021 - 7th International Conference on Information and Communication Technologies for Ageing Well and e-Health
the requirements engineer, the quality engineer, the
project manager, and the gerontology specialist
perform the requirements elicitation phase, which
delivers the requirements specification document-
oriented to the interface design as an artifact.
Additionally, the vocabulary selection, message
creation, and pictogram selection guides can be used
by the gerontology specialist and domain expert.
3.1.3 Prototype Design
This activity is shown in Figure 1 (3); the quality
engineer, the project manager, and the domain expert
carry out a conceptual design based on the documents
generated in the analysis phase. Additionally, the
interface designer and the quality engineer carry out
the design and prototyping using a prototyping tool.
Design is guided by usability and accessibility criteria
guidelines; also by an organization and design guide of
grids suitable to adapting pictograms on the interface.
3.1.4 Prototype Evaluation
This activity is shown in Figure 1 (4). Within it is the
prototype verification and validation tasks, which the
project manager and quality engineer execute. In this
phase, it is important to ensure the prototype's quality
and is considered purely iterative in conjunction with
the prototype design phase. Once a quality product
has been achieved and meets the proposed
requirements, it is considered that the objective of the
method has been achieved.
3.1.5 Implementation
This activity is shown in Figure 1 (5), from the
designed prototype, and through a software
engineering process, a functional interface is
implemented to adapt it in the AAC system.
3.2 Artifacts in the UIAAC Method
3.2.1 Document of User Needs and Problems
This document specifies the needs and problems that
the user faces. Each need is analyzed to understand
the situation. Here the user is located, and from this,
they can have a global idea about the type of system
that the user needs.
3.2.2 User Profile
The user profile is defined based on knowing in detail
the characteristics of the person to whom the interface
is aimed. Among them is information about the
motivations and aspirations of the graphical interface
and the AAC system. It is also considered essential to
know the degree of familiarity that the user has with
the different technologies.
3.2.3 Scenario Definition
Having the setting defined, it is essential to frame the
product's use or its need for use (Hassan, 2015).
Documenting the place where the actions will occur
is important because it allows the project to be
tailored to a specific situation; in addition to that, the
scenario represents the real situation where the user
will interact with the AAC system to meet an
3.2.4 Project Structure
The project structure is a document that defines the
activities and how they will be grouped and
coordinated to guide the design process of the AAC
interface aimed at older adults. It also defines each
phase's workgroups, roles, and activities to optimize
the resources and time to invest in each phase. The
objectives and limitations of the project are also
established here. Finally, the work structure is
designed based on the definition of the scope and
should be guided by the domain expert's observations
in the AAC and built by the project manager.
3.2.5 Requirements Specification
As a product of the requirements elicitation, a
requirements specification document is obtained.
This should be clear, unambiguous, easy to
understand, complete, and consistent. This document
is organized by Somerville's structure and includes
the functional and non-functional requirements of the
3.2.6 Definition of Vocabulary and Messages
This document contains the domain vocabulary
characteristics chosen to adapt it in the interface. It
can also contain a list of common messages that help
to synthesize an idea to increase the communication
skills of the older persons in particular everyday
3.2.7 List of Pictograms
Once the domain, vocabulary list, and messages of
the AAC system have been defined and based on
selection criteria of pictograms aimed at the older
persons, the most suitable pictograms can be chosen
UIAAC: A Method for Designing of Graphical User Interface for Augmentative and Alternative Communication
to be integrated into the interface. It is essential to
define and validate that pictograms increase the user's
ability to communicate without using verbal
3.2.8 Conceptual Design
It is a document that refers to the decisions regarding
the graphic interface design and the interface model.
Represents a plan or skeleton that allows
communication from the beginning, how the interface
will interact. Conceptual design is the tool used to
communicate the intention of our design.
3.2.9 Initial Prototype
It is a visual representation of the conceptual design
and helps verify that the interface is designed
according to the expected requirements. It can be
designed in different tools, and its purpose is to offer
a tangible product that can be evaluated and accepted
for later implementation. It usually is functional, but
its features are limited.
3.2.10 Version List and Final Prototype
This document contains all the versions created of the
prototype and includes the changes and
improvements with respect to its predecessors are. It
is the final approved and validated version of the
prototype, with which the AAC system will be
3.3 Guidelines in the UIAAC Method
One of the advantages of this method is that it
includes a series of guides that provide content so that
some phases are completed efficiently and, therefore,
a final high-level product is designed.
3.3.1 Requirements Template
Requirements elicitation has the objective of
producing a requirements specification document that
satisfies the user's expectations and the interested
parties. For this it is necessary to use requirements
collection templates. Durán & Bernardéz (2000),
propose templates for obtaining product objectives,
functional and non-functional requirements.
3.3.2 Vocabulary, Message and Pictogram
Selection Guides
This guide presents a series of considerations for the
selection of vocabulary, messages and pictograms to
be displayed on the interface. These guides allow you
to analyze the situations in which the user needs help;
in this way, it is possible to understand the scenario
and develop the vocabulary, messages and
pictograms appropriate to the situation.
This is possible through some considerations and
recommendations proposed by institutes specialized
in the domain of AAC.
3.3.3 User Person Template
UIAAC recommends the use of the personal data
template. To obtain a UCD, the design must be based
on real information about the product's audience, with
specific information obtained through user research
3.3.4 Project Management Guide
Every project must be guided by general planning;
Bedini & Guerra (2005) propose a project structure
composed of a general description of the project that
includes the objectives and restrictions; organization
of the project, in which the participants and their
activities are organized; calendar, containing
estimates and a schedule for project tasks.
3.3.5 Usability and Accessibility Criteria
Some usability criteria can be considered for a design
to be of quality. Mascheroni & Greiner (2012),
Sánchez (2011), and Sastoque et al. (2016) provide
usability guidelines (e.g., ease of learning,
satisfaction, efficiency, visualization), which will
serve as a design guide for the prototype designer.
UIAAC also includes a guide with accessibility
criteria, which should be considered to guide the
design towards the older persons. Table 1 presents an
extract from the guide, with some accessibility
Table 1: Accessibility Criteria.
Type Description
Consider interacting with traditional
media (e.g., keyboard, mouse, touch
Consider aspects such as language and
reduction of users’ tasks.
visual and
- Text size.
- Text style: depends on the user.
- Contrast and color
- Multimedia: intuitive sounds can be
added if necessary.
ICT4AWE 2021 - 7th International Conference on Information and Communication Technologies for Ageing Well and e-Health
3.3.6 Organization and Design of Grids
It is essential to consider that a grid must be designed
respecting the considerations and specifications of the
end-user. UIACC contains a guide with different
types of grid organization and design to create a
model according to user needs.
In this section, the five activities involved in the
UIAAC method have been applied to design an
interface prototype for an AAC web system to assist
in communication problems for an older adult. Each
of these activities is described at a high level and
detailed in Figure 2.
Figure 3 shows the AAC system with its AAC
interface implemented. This app is available at the
following URL: https://n9.cl/mc3l
A solution interface was built following the UIAAC
method, and it was evaluated through a case study. It
follows the following activites proposed in the
Runeson et al. (2012) methodology: i) design, ii)
ethical considerations, iii) preparation for data
collection, iv) collecting evidence, v) analysis of
collected data and reporting, and vi) threats of validity
5.1 Design
This case study's main objective is to know health
personnel and end-users perceptions regarding
interface pictograms app created for older people. In
this context, the research questions are i) How does
the psychologist perceive the technological solution's
clinical utility? Moreover, ii) How does the end-user
perceive the usefulness of the technological. The case
study method is holistic-multiple, and the units of
analysis are presented in Figure 4.
Figure 3: Interface pictograms app.
Figure 4: Holistic-multiple method.
5.2 Ethical Considerations
Although Amschler & Pradhan (2001) points out a
case study relies primarily on trust between the
investigator and the case, some explicit prevention
measures have been considered to prevent future
problems, mainly because the older adults belong a
vulnerable group.
In this case study, the ethical factors considered
are: i) informed consent with both the older persons
and their primary caregivers, ii) the approval of an
ethics committee for this type of test, iii)
onfidentiality, and iv) feedback. Moreover, due
COVID-19 pandemic context, all health security
protocol was considered by the Clinical psychology.
5.3 Preparation for Data Collection
Two surveys have been designed based on the
technology evaluation model (TAM) proposed by
Davis (1985). This model consists of evaluating the
Perceived Ease Of Use (PEOU), the Perceived
Usefulness (PU), and the Intention To Use (ITU) in
the future. The designed surveys were focused on the
elderly and the health expert. This questionnaire, as is
shown in Appendix 1, uses a 5-point Likert scale.
5.4 Collecting Evidence
In a first step, the interface pictogram app was
presented by the Clinical psychologist to older adult
in his home (see Figure 6). Then, the surveys were
filled out by all participants.
5.5 Data Analysis and Results
By analyzing the results, it is found that they allow
answering the case study questions. In open
questions, older adult agree that the interface is useful
for communication. At the same time, the expert
considers that obtain new ways to interact with this
kind of people is essential for healthy social
interaction. Figure 5 shows the overall results of
PEOU, PU, and ITU. In general, Clinical
UIAAC: A Method for Designing of Graphical User Interface for Augmentative and Alternative Communication
psychologist and older adult mention that the
interface solution is easy to understand; besides, this
technological input can reduce communication time
and effort. They also rescue that it is a useful input
since it allows the patient's communication; therefore,
it could be used in the future.
Figure 5: Results of the case study: user perceptions.
Figure 6: Data collecting.
5.6 Threats of Validity
The following threats to validity are discussed to
reveal their potential interference with this study.
5.6.1 Construct Validity
Construct validity refers to the relation between the
theory behind the case of study and the empirical
reality. To analyze whether the operative measures
studied represented what the researchers had planned
to investigate and what they investigated. For this
step, validated questionnaires were used, which have
an ideal Cronbach's alpha; thus, the interview
questions' constructs will be interpreted in the same
way by the researcher and the people interviewed.
5.6.2 Internal and External Validity
Depending on how the subjects in a group are
selected, the selection effects may vary. In this study,
the age, pathology degree, and previous experience
that the participants have with technology influence
the ease of use when using the proposed solution.
For the external validity, the selection of the
Figure 7: Steps to design a graphical interface for AAC systems using UIAAC.
Older Adult Clinical psychologist
ICT4AWE 2021 - 7th International Conference on Information and Communication Technologies for Ageing Well and e-Health
sample of individuals who participated was made at
convenience. Due to the COVID-19 pandemic, access
to the elderly population with disabilities is restricted.
5.6.3 Reliability
The evidence chain was carried out respecting the
data's literality from the interviews to the analysis.
Moreover, the qualitative responses were quantified
using a Likert scale to avoid introducing
interpretation bias.
The UIAAC method considers design aspects for
older adults based on protocols and standards for
designing graphical interfaces for AAC systems that
integrate pictograms. The design and creation of
prototypes are oriented in the analysis of domains,
end-user documents, and observations of the
specialist in gerontology; this allows for a correct
This method is designed to be applied within
software engineering processes, specifically for
designing graphical interfaces of AAC systems. A
web system has been built to help improve older
adults' cognitive abilities; where the interface has
been designed with this method, it has been possible
to test the feasibility of the method. The AAC system
has used a psychologist for evaluation and an older
adult to use the app. The results show that the app is
perceived as easy to use and useful. Finally, as future
work, the UIAAC method will be studied in depth to
expand and detail each phase's activity, guide, and
This work is part of the following research projects:
“Fog Computing applied to monitor devices used in
assisted living environments; case study: platform for
the elderly people”, “Design of architectures and
interaction models for assisted living environments
aimed at older adults. Case study: playful and social
environments” and “Integration of New Technologies
for the Design of Cognitive Solutions in Ambient
Assisted Living for Elderly People: Evaluation of
Attention and Memory Areas”. Therefore, we thank
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