Biomedical Engineering Reference
In-Depth Information
is composed of the evaluator's expertise and knowledge. Still, two other components influ-
ence the evaluation process:
1. The international accessibility and design guidelines that determine the standards
the evaluator has to take into account when evaluating the interface properties
(accessibility and usability).
2. The techniques actually applied by the evaluator for evaluating accessibility,
usability, and satisfaction. The use of a specific technique forces the evaluator to
adapt his or her mental model to the perspective endorsed by the technique. In
other words, because the specific techniques used for the evaluation influence the
mental model adopted by the evaluator, the evaluation outcome largely depends
on the applied techniques.
At the end of the evaluation process, the evaluator should have obtained the level of
accessibility; the level of usability; the degree of satisfaction; and, as indirect estimation, the
measure of the distance between the designer's and the user's mental model as the distance
between the technology functions—the conceptual model created by the designer's mental
model—and the function of technology that is really perceived by users. The evaluators
obtain the measure of the interaction distance matching the errors of the object, analyzed
by expert analysis (objective-oriented) with the problems observed by the users' evaluation
(subjective-oriented). This match shows the distance between the interaction imagined by
the designer for a hypothetical user and the interaction perceived by the real user.
15.4 Example of the UX Concept Application
in Design Systems for Rehabilitation
15.4.1 UX in the Assistive Technology Assessment Process
By using the integrated approach in the rehabilitation system, we might consider that the
UX evaluation does not concern only the users' experience with an assigned technology,
but also the users' experience of the whole assistive technology assessment (ATA) process
functioning (i.e., action of the center for technical aid), that can be considered as the degree
of accessibility and usability of the service.
In fact, the assignation process of a center for technical aids may be considered as a sys-
tem interface itself by which a user can reach a goal. In this sense, we can evaluate the UX
experience of the ATA process on two levels (see Figure 15.5):
1. The first level concerns the UX evaluation of the ATA process (i.e., degree of
accessibility and usability in the relationship between the users and the center
for technical aids). This level of evaluation is linked to managerial solutions
that are able to grant access to and use of the service. Even if this level is far
from the classic use of the UX evaluations, concerning the economical and man-
agerial dimensions, it is necessary for guaranteeing the correct evaluation of
the assistive technology (AT) (second level). Indeed, the design of a good ATA
process is the best way to obtain a satisfied match between user and technology.
