Publication
THESEUS CTC-WP4 Usability Guidelines for Use Case Applications
Daniel Sonntag; Colette Weihrauch; Oliver Jacobs; Daniel Porta
Technical Report, Bundesministerium für Wirtschaft und Technologie, DFKI Technical Memos, Vol. V 1.5, 4/2010.
Abstract
Usability Guidelines for Use Case Applications serves as an introduction to the
general topic of usability, i.e., how user-friendly and efficient a THESEUS prototype
is. In these guidelines, we emphasize the importance of usability testing,
particularly during the development of a given THESEUS prototype. We discuss the
many advantages of testing prototypes and products in terms of costs, product
quality, and customer satisfaction. Usability testing can improve development
productivity through more efficient design and fewer code revisions. It can help to
eliminate over-design by emphasizing the functionality required to meet the needs
of real users. Design problems can be detected earlier in the development process,
saving both time and money. In these Guidelines we provide a brief overview of
testing options, ranging from a cognitive walkthrough to interviews to eye
tracking. Different techniques are used at different stages of a product's
development. While many techniques can be applied, no single technique alone can
ensure the usability of prototypes. Usability is a process with iterative steps,
meaning the cycle is repeated but in a cumulative fashion, similar to software
development.
In order to test, a prototype must be available and we devote some time in the
Guidelines to an overview of different tools and ways to build the necessary
prototypes. We also describe some options such as paper prototyping, prototypes
from Visio, PowerPoint, HTML, Flash and others, and working prototypes (Java,
C++, etc.) before addressing the actual tests. Before any testing is conducted, the
purpose of the test should be clarified. This will have considerable impact on the
kind of testing to be done. A test plan should also be written before the start of the
test which considers several different aspects including, for instance, the duration
of the test, where it will take place, or who the experimenter will be. A pilot test is
also recommended to avoid misunderstandings and other problems during the
actual test. In this context, the Guidelines also discuss other important aspects such
as budget, room set-up, time, and limitations of the experimenter and test subjects
themselves.
To provide an overview of some of the projects THESEUS is concerned with in the
context of usability, we supply explicit recommendations that result in proposed
scenarios for use cases in the Guidelines. The THESEUS program consists of six use
cases: ALEXANDRIA, CONTENTUS, MEDICO, ORDO, PROCESSUS, and TEXO. In
order to come up with the different testing scenarios, each of which has specific
design and testing recommendations, we first extracted some substantial
information from the different use cases in different user settings: we discerned
between those who will use the system, where they will use the system, and what
they will do with the system. After considering the results, we determined that the
THESEUS program works with seven different scenarios. We provide a decision
tree that leads to specific recommendations for designing and testing with
prototypes for each of the different scenarios and user settings. General
recommendations concerning various input methods, the design, and the testing
itself have also been included in the Guidelines. Following that, we emphasize what
we find important for the design and testing of each of the seven testing scenarios.
We address, for instance, the appropriate input method (keyboard, mouse, speech,
etc.), according to the type of test subject (e.g., administrator or mobile user), or
also which prototype could be used for the usability test.
We will also challenge the usability of traditional usability guidelines. Oftentimes,
guideline descriptions and explanations are unsatisfactory, remaining vague and
ambiguous in explanation The Guidelines close with an extensive list of
recommended further information sources.