=Paper=
{{Paper
|id=Vol-3356/paper3
|storemode=property
|title=What Is the Difference between Usability in ISO 25000 and Usability in 9241-11? - The Term “usability” as Part of the Product Quality Model Used in the SQuaRE Series in Contrast to the Term Usability in ISO 9241-11-(poster)
|pdfUrl=https://ceur-ws.org/Vol-3356/paper-03.pdf
|volume=Vol-3356
|authors=Shinichi Fukuzumi,Thomas Geis,Jonathan Earthy
|dblpUrl=https://dblp.org/rec/conf/apsec/FukuzumiGE22
}}
==What Is the Difference between Usability in ISO 25000 and Usability in 9241-11? - The Term “usability” as Part of the Product Quality Model Used in the SQuaRE Series in Contrast to the Term Usability in ISO 9241-11-(poster)==
https://ceur-ws.org/Vol-3356/paper-03.pdf
What Is the Difference between Usability in ISO 25000 and
ISO/IEC 9241-11?
- The Term “usability” as Part of the Product Quality Model Used in the SQuaRE
Series in Contrast to the Term Usability in ISO 9241-11-
Shin’ichi Fukuzumi 1, , Thomas Geis 2 Jonathan V Earthy 3
1
RIKEN, 15F, 1-4-1 Nihonbashi, Chuo-ku, Tokyo, 103-0027, Japan
2
ProContext, Cologne, Germany
3
Lloyd’s Register Group Limited, London, UK
Abstract
The ISO/IEC 25000 SQuaRE series of standards (System and software Quality Requirements
and Evaluation) deals with quality of systems and software. In ISO/IEC 25010:2011, “usability”
is described as a product quality characteristic. On the other hand, “effectiveness”, “efficiency”
and “satisfaction” exist as quality characteristics within the quality-in-use model. However, the
usability definition used in ISO/IEC 25010 is “degree to which a product or system can be used
by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a
specified context of use”. As usability for quality characteristics in product quality does not
include effectiveness, efficiency and satisfaction. So, there is a contradiction between usability
definition and quality characteristics of usability in product quality. This paper describes the
meaning of the two “usability” terms, and proposes “interaction capability” as the alternative
term for “usability” in product quality to eliminate confusion for the readers of the standard.
Keywords 1
usability, software engineer, quality in use, product quality, interaction
1. Introduction shows the quality in use model as describes in
ISO/IEC 25010: 2011 [2]
The ISO/IEC 25000 SQuaRE (System and
software Quality Requirements and Evaluation)
series comprises international standards for
systems and software quality. There is a quality
model division that is one of five main divisions
and extension division. There are four quality
models. including“ data quality”, “service
quality”, “product quality” and “quality-in-use”.
Figure 1 shows the structure of SQuaRE series.
In this series, two of four quality models, that
is, product quality model and quality in use model
are described in ISO/IEC 25010:2011. Figure 2
shows the product quality model and figure 3
Figure 1. The architecture of the SQuaRE series
[1]
4th International Workshop on Experience with SQuaRE Series and
its Future Direction, December 06, 2022, Tokyo, Japan
EMAIL: tsnaka@shibaura-it.ac.jp (A. 1);
alessandro.simonetta@gmail.com (A. 2)
ORCID: 0000-0002-9721-4763 (A. 1); 0000-0003-2002-9815
(A. 2)
© 2022 Copyright for this paper by its authors. Use permitted under Creative
Commons License Attribution 4.0 International (CC BY 4.0).
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Figure 2 Product quality model including usability as a quality characteristic and its sub-characteristics [2]
Figure 3 Quality in use model [2]
In figure 2, we find the term “usability” as one of effectiveness, efficiency and satisfaction in a specified
the characteristics of product quality. On the other hand, context of use”. Figure 4 explains that the outcome of
we find the terms “effectiveness”, “efficiency” and “use” in context of use is usability in terms of
“satisfaction” as quality characteristics of the quality in effectiveness, efficiency and satisfaction. In figure 4,
use model in figure 3. In ISO 9241-11, usability is “use” is emphasized.
defined in terms of effectiveness, efficiency and
satisfaction. So, the same term “usability” is used in
both standards, but the meanings are different.
This paper describes the difference between the
definitions and proposes an alternative term to
“usability” in product quality.
2. Meaning of “usability” as defined in
ISO 9241-11
Figure 4 shows the concept and definition of
usability as defined in ISO9241-11 [3].
In ISO 9241-11, usability is defined as the “extent Figure 4. Usability concept (ISO9241-11,
to which a system, product or service can be used by modified)[4]
specified users to achieve specified goals with
There are other popular usability definitions. For quality are taken from ISO9241-110
example, Nielsen[5] defined usability in terms of (“Interaction principles”). From this, these
five characteristics, including “easy to learn, i.e., quality sub- characteristics are deeply related to
learnability”, “efficient to use, i.e., efficiency”, “interaction”. So, we propose the term
“easy to remember, i.e., memorability”, “few “interaction capability” as a replacement term for
error” and “subjectively pleasing satisfaction”. “usability” for quality characteristics in the
Jordan[6] defined usability in terms of product quality model.
“guessability (of interaction), “learnability” (of
interaction), and so on. These definitions are both 4. Conclusion
related to user system interaction. They are
focused on interface design for interaction, e.g.,
“learnable interaction process”, “guessable This paper describes the meaning of two
“usability” terms in ISO/IEC 25010 and ISO
button for intended operation” or “font size for
9241-11. “Interaction capability” is proposed as
minimizing reading errors”. As these definitions
the alternative term to “usability” for the product
focus on “ease of interaction”, , there is a
quality model. Irrespective of whether this
difference between these definitions and the ISO
definition used in ISO/IEC 25010 and ISO 9241- proposal will be accepted for new versions of
11. ISO/IEC 25010, we have to clarify the
misunderstanding between the capability of
product attributes to serve as prerequisites for
3. Proposal for an alternative term usability (“interaction capability”) as defined in
to not confuse readers of the software engineering area and usability itself
as defined in the ergonomics area
Standards of the SQuaRE series
As described in section 2, the sub- 5. References
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ws.org/Vol-3114/paper-06.pdf, 2021
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Some of the quality sub-characteristics of
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