Page contents
Overview
Background
Purpose of the trial
How the users, tasks and measures were selected
Summary of CIF results
Benefits to Ericsson from using the CIF
Benefits to Electrolux from using the CIF
Discussion
Overview
In order to support the procurement process, the common industry
format (CIF) for usability testing has been used to obtain usability
metrics at Ericsson and Electrolux in Sweden. First, the current
Ericsson system was tested using the CIF to obtain a baseline value
for usability, which resulted in an usability requirements document.
The document required information about the way in which the supplier
had developed the product and detailed information about user performance
and user satisfaction metrics. Secondly, the likely supplier of
a new system called WEBRES developed by Electrolux was tested and
the results compared to the requirements document.
Ericsson was investigating the purchase of a new interface to the
existing travel management system - RES. The current text-based
interface no longer supported users task demands and requirements
effectively and it was not found easy to use. RES was used by about
25% of Ericsson employees although the goal was to increase this
percentage significantly. It was a complete system that supported
business travel management both nationally and internationally.
Ericsson did not wish to make significant changes to the underlying
system. They looked to a number of potential suppliers who were
able to provide a new interface, which would enhance the efficient
and effective use of the existing system. At this time, the prime
candidate supplier was Electrolux. They used essentially the same
travel management system as Ericsson but had developed in-house
interface solution - WEBRES. This interface was a possible replacement
to the current RES interface.
At this time, Ericsson had not considered any usability issues
during the purchase process. There was no objective data about user
performance/subjective assessment using RES and there was no usability
requirements document. The PRUE project was able to support the
procurement process by conducting summative usability testing on
RES using the CIF format. The objective was to obtain user performance
and satisfaction metrics of the RES interface through formal user
testing. The results from testing led to a usability requirements
document against which potential suppliers could be assessed. Subsequently,
similar testing using the CIF was conducted on Electrolux's WEBRES.
The test results were then compared and contrasted to the usability
requirements document prepared by Ericsson.
PRUE has been of great value to Ericsson. Without PRUE, usability
issues would not have been included in this procurement process.
PRUE has resulted in a usability requirements document for a new
interface to RES, which was regarded as a new and positive input
to the Ericsson decision process when selecting a supplier organization.
The usability requirements were regarded as a good compliment to
the existing functional and technical specifications. Further, there
were benefits of increased understanding of user performance using
the current system (poor performance is a large cost in time to
Ericsson), an objective understanding of what users thought of the
current system and what they require from the new.
From the supplier perspective, Electrolux have been able to understand
the performance/ satisfaction related Ericsson requirements for
WEBRES. The CIF for usability testing enabled them to assess how
WEBRES compared to the Ericsson requirements, and it has provided
a clear indication of what improvements need to be made to the interface
design.
Background
At the start of the PRUE project, Ericsson was investigating the
purchase of a new interface to the existing travel management system
- RES. The current text-based interface no longer supported users
task demands and requirements effectively and it was not found easy
to use. The interface lacked overview of the travel claim and did
not support the wide variation and complexity of travel carried
out today. There are usability problems, such as use of many codes
and abbreviations, plus poor readability.
RES was used by about 25% of Ericsson employees although the goal
was to increase this percentage significantly. It was a complete
system that supported business travel management both nationally
and internationally. Further, managers use RES to approve and attest
business travel and expenses, financial controllers use it to review
travel claims and RES is connected to other financial systems to
ensure that staff are reimbursed quickly and efficiently for travel
expenses. It also provides extensive statistical travel data for
the Ericsson Enterprise
As Ericsson did not wish to make significant changes to the underlying
system, they looked to a number of potential suppliers who were
able to provide a new interface, which would enhance the efficient
and effective use of the existing system. At this time, the prime
candidate supplier was Electrolux. Electrolux used essentially the
same travel management system as Ericsson but developed in-house
interface solution - WEBRES. The interface was an Internet solution
and a possible replacement to the current RES interface.
At this time, Ericsson had not considered any usability issues
during the purchase process. There was no objective data about user
performance/subjective assessment using RES and there was no usability
requirements document. Ericsson agreed to participate in the PRUE
trial application to assess the benefits of using the CIF in this
procurement process and also to assess the benefits of using summative
usability testing in general within the organisation during procurement.
As the prime supplier organisation at this time, Electrolux agreed
to participate in the trial application. Users had not formally
tested WEBRES for usability.
Within the context of this process, PRUE has carried out five main
activities:
A stakeholder meeting to present the importance of usability and
specify the intended context of use of the Ericsson travel management
system.
A formal user evaluation of the existing system - RES - according
to CIF to provide measures of usability as baseline requirements.
A usability requirements document (not in the public domain) to
be used by Ericsson when assessing possible alternatives to RES.
The document required information about the way in which the supplier
had developed the product and required the supplier to provide detailed
information about user performance and user satisfaction metrics.
A formal user evaluation of the Electrolux travel management system
- WEBRES to establish whether the Ericsson requirements had been
met.
An initial benefit analysis of using the CIF to the consumer organisation
and the supplier organisation.
Purpose of the trial
The main objective of the trial application was to evaluate whether
one possible successor to the existing travel management system
at Ericsson, met specified usability requirements. This was demonstrated
by applying the common industry format for usability testing during
this procurement process to the current Ericsson system (RES) first
and then the Electrolux system (WEBRES).
First, user performance and satisfaction metrics of the current
RES interface were obtained through formal user testing following
the CIF for usability testing. The test results were fed into a
usability requirements document in the form of usability goals and
against which alternative systems/interfaces could be judged.
Subsequently, using very similar formal user testing following
the CIF, user performance and satisfaction metrics of the WEBRES
user interface. The test results were compared to the Ericsson usability
requirements document. This provided Ericsson with a further decision
basis upon which to assess the Electrolux product.
How the users, tasks and measures were selected
Usability metrics
The metrics and measures defined in the CIF were used; the effectiveness
parameter - Task completion (%), the efficiency measure - task time
(min), number of errors and number of assists.
User satisfaction was rated using the standardised questionnaire
- SUMI for the RES test and WAMMI for the WEBRES test. Results of
SUMI and WAMMI can be correlated to each other to make comparison
of results possible.
Participants
Typical users from the Ericsson Enterprise carried out the testing.
A pilot test was carried out at the beginning of the test sessions.
Test participants were selected according to two criteria. Firstly,
they were Ericsson employees. Secondly, they were familiar with
the travel management process and completed travel management accounting
procedures up to five times per year. One key group was 'Consultants',
who use the travel management system occasionally. Another group,
secretaries who help others create their travel claims reports,
was included. They were experienced and efficient using the system.
Selection of users for the tests was done via a large e-mail mail
shot to Ericsson employees. Test participants familiar with RES
were selected according the defined user profile (8 for RES and
7 for WEBRES). The users tested fulfilled the user profile, although
some claimed more than 5 business trips per year. Travel varies
depending on project work.
The tests were conducted in Swedish, the tasks were in Swedish
and users were Swedish. RES and WEBRES use Swedish primarily, although
parts of them are in English. The corporate language is English.
Tasks
After some interviews with relatively experienced business travellers,
selected tasks for the study were the most frequent travel management
tasks at Ericsson Enterprise. Tasks were typical and not complex.
Business trips over multi-destinations and long time periods were
not selected. The tasks are summarised below:
Task 1: Create a travel application (not applicable to WEBRES)
Task 2: Create a foreign travel report - return travel to Vienna.
Task 3: Create a travel report for domestic travel with train and
rental car.
Task 4: Create a travel report for various own car-related expenses.
Users were provided with 'simulated' travel vouchers/receipts for
each of the tasks. As users had not actually experienced the business
trip, they were given some time to understand the information before
starting on the task.
Procedure
The design of the test followed a logical sequence of events for
each user and across tests. One person ran the test and one observed.
Other persons related to the project or the development team at
Ericsson and then Electrolux observed the testing. The testing procedure
was as follows:
- User were greeted and offered refreshment.
- Users were given information about the goals and objectives
of the test.
- Users were asked a set of predefined background questions prior
to the testing
- Users were then given a series of clear instructions specific
for the test.
- Users were asked to complete the four tasks in order quickly
and efficiently.
- Users were asked to complete a SUMI/WAMMI questionnaire direct
after completing the last task.
- Users were asked a set of predefined background questions after
the testing
- Users thanked and for their participation were given cinema
tickets worth 160 SEK.
As users were familiar with the product and the process of travel
management there were no nondisclosure agreements, form completion,
warm-ups or pre-task training.
Summary of CIF results
All users had problems in performing the tasks and they made many
mistakes. Some of the mistakes were minor, some were easily corrected
with/without assistance and some were so severe that the user did
not succeed at all. In the interviews preceding the tests many users
indicated that they normally have problems with their travel reports
after business trips.
|
|
RES
|
WEBRES
|
|
Task #
|
Unassisted Task Effectiveness [(%)Complete]
|
Task Time (min)
median
|
Errors
|
Assists
|
Unassisted Task Effectiveness [(%)Complete]
|
Task Time (min)
median
|
Errors
|
Assists
|
|
1
|
80
|
3,34
|
11
|
4
|
-
|
-
|
-
|
-
|
|
2
|
57
|
10,47
|
20
|
1
|
50
|
22,00
|
13
|
1
|
|
3
|
63
|
7,45
|
8
|
0
|
67
|
7,50
|
7
|
1
|
|
4
|
58
|
2,06
|
3
|
0
|
67
|
5,25
|
5
|
0
|
Table
1: Summary of usability metrics by user.
The tables above show no major differences in user performance
between the two tested systems except for task time and satisfaction.
Error rates were unexpectedly high in both systems. The number of
assists required when testing the current system was also unexpectedly
high. The web-based WEBRES was slower in two cases out of three
but was still perceived as better by the users as indicated by the
satisfaction measurements.
User satisfaction was rated using the standardised questionnaire
- SUMI for the RES test and WAMMI for the WEBRES test. Results of
SUMI and WAMMI can be correlated to each other to make comparison
of results possible.
|
RES
|
WEBRES
|
|
|
Median
|
Median
|
|
|
Affect
|
17
|
30
|
Attractiveness
|
|
Control
|
28
|
60
|
Controllability
|
|
Efficiency
|
22
|
34
|
Efficiency
|
|
Helpfulness
|
21
|
25
|
Helpfulness
|
|
Learnability
|
29
|
23
|
Learnability
|
|
Global
|
20
|
45
|
Global Usability
|
|
The
overall score for RES on the SUMI satisfaction questionnaire
was 20. The value of 50 is the industry average
SUMI score.
|
The
overall score for WEBRES on the WAMMI satisfaction questionnaire
was 45. The target value of 50 is the industry
average WAMMI score.
|
Table 2:
User satisfaction results – a comparison.
While caution should be used when comparing the subjective assessment
results, it is clear that RES performed poorly as it was not liked
by users despite the fact that they used RES relatively regularly.
WEBRES on the other hand performed quite well on the WAMMI scale
with a high controllability value. Effort would need to be taken
to improve attractiveness and efficiency values. This relatively
high subjective value was interesting as user performance was actually
slightly lower than RES.
Neither systems were acceptable as the global scores of 20 and
45 were less than the average industry average values of 50 for
the standardised SUMI and WAMMI questionnaires. In terms of requirements,
Ericsson would like a replacement system/interface to be at lest
as acceptable as the industry average, which means having a score
of at least 50.
|
|
RES
|
WERRES
|
|
Mean task
completion rate for all tasks
|
55%
|
56%
|
|
Mean number
of total errors per user
|
5
|
3.57
|
|
Mean total
task time
|
28 min
|
34 minutes
|
|
Completion
rate efficiency
(completion rate per minute)
|
2.9%/min
|
3.0%/min
|
|
Global score on the SUMI/WAMMI user satisfaction questionnaire
|
20 (SUMI)
|
45 (WAMMI)
|
Table 3:
Summary the overall results by metrics.
The overall results presented in the table above indicate that
WEBRES performs slightly better than RES (high overall task completion,
few errors). However, mean total task time was longer. There was
no significant difference for completion rate efficiency. Users
preferred the WEBRES interface.
In conclusion, while users preferred WEBRES they did not perform
as well as expected when using it. The results indicate that the
design of the WEBRES interface needs to be improved so that it supports
typical tasks more efficiently.
Benefits to Ericsson Enterprise from using
the CIF
Ericsson assesses that the work done within the PRUE project so
far has proven to be of great value.
Initial testing lead to the creation of a usability requirements
document for the new travel management system. This was regarded
as a new and positive input to the Ericsson decision process when
negotiating with Electrolux over the new interface to the current
system. The usability requirements are regarded to be good compliment
to the functional and technical specifications.
The usability requirements document will support Ericsson during
purchase negotiations with Electrolux, or any other supplier of
travel management systems.
Testing using the CIF has led to increased understanding of user
performance and subjective assessment in current RES system. This
has been considered in internal financial terms as poor performance
results in a substantial cost to Ericsson.
Testing has given Ericsson an clearer understanding of what users
think of the current system and what they require from the new.
Ericsson is considering products from other supplier organizations
than the one tested, and the usability requirements document will
be one factor supporting the assessment of these alternatives.
There is an interest from Ericsson to continue using the CIF as
a basis summative testing during procurement and requirements work
both within this specific project and in general across the organisation.
Ericsson will support the proposed dissemination activity plan.
Benefits to Electrolux from using the
CIF
Electrolux assesses that the PRUE project has led to the following
benefits :
Testing of RES using the CIF and the creation of a usability requirements
document for the new travel management system has helped Electrolux
understand Ericsson usability requirements and the importance of
user performance and subjective assessment.
Testing WEBRES using the CIF has enabled Electrolux's to compare
the performance of their product against the usability requirements
document.
Testing has given Electrolux an clearer understanding of user performance
and user satisfaction of WEBRES. It has provided an indication as
to how efficiently WEBRES supports the basic and typical tasks.
Testing has given them a basis upon which to improve the WEBRES
interface.
Discussion
Summative usability testing using the CIF has advantages to both
consumer and supplier organisations during procurement. It one of
the most effective ways to enrich the consumer's requirements document
with objective user performance and satisfaction metrics (based
on the existing system/product used).
Consumers will find that it provides an important input when evaluating
potential competitive products from a number of supplier organisations
during the procurement of a new system/product.
By using the CIF test structure, suppliers are able to demonstrate
that their product complies to the usability metrics defined in
the requirements document. It will also provide them with information
as to how to improve the product/system from the user/usability
perspective. It will also encourage suppliers of products and systems
to apply principles of user-centred design during the development
of their product/system.
Last updated
12-Mar-02
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