4. Does it matter?
"The extent to which a product can be used by specified
users to achieve specified goals with effectiveness,
efficiency, and satisfaction in a specified context of use."
ISO 9241-11
9. Elements of Usability
Utility = whether it provides the features you need.
Usability = how easy & pleasant these features are to use.
Useful = usability + utility.
Jakob Nielsen
14. Usability errors
• Hospital system:
• 22 ways of dispensing the wrong medication to patients.
• Most of these flaws are classic usability problems.
Medical Usability: How to Kill Patients Through Bad Design
JAKOB NIELSEN
Poor Readability
Patient names in a small font
easy to select the wrong patient. Memory Overload
Patient’s medications presented on up to twenty screens 72%
of staff uncertain about medications and dosages because of the
difficulties in reviewing a patient's total medications.
Date Description Errors
Specifying medications for „tomorrow” entering
orders after midnight caused that patients would
miss a day's medication.
17. What is the problem?
You know the rules.
You can recognize poor usability.
You are doing usability tests.
It’s enought, right?
ISO 9241 Ergonomics of
Human System Interaction
Nielsen’s
heuristics
Style
guidelines
Krug’s
laws
21. Testing is not enough
„Prevention is better than cure.”
― Desiderius Erasmus
„Intellectuals solve problems, geniuses prevent them.”
― Albert Einstein
Design
for
usability
Evaluate
for
usability
22. Planning and engineering
Usability is not just a matter of intuition.
Usability is not a „nice to have” factor.
Usability can be planned and designed.
Usability is an area of engineering.
23. Usability engineering
A field concerned with
human-computer
interaction and specifically
with making human-
computer interfaces that
have high usability or user
friendliness
24. The proces of Usability Engineering
Concept Planning
Understanding
needs
Requirements
Analyse
requirements
Design/
development
25. Concept
• Best practices:
• Envisioning opportunities
• Context of use of systems.
• System concept.
• System scoping
• The objectives of the system.
• The scope of the context of use.
Envisioning
opportunities
System
scoping
26. Concept
Know your users.
Know their goals, skills, preferences, and tendencies.
“Obsess over customers: when given the choice between obsessing over competitors or
customers, always obsess over customers. Start with customers and work backward.”
– Jeff Bezos
27. Concept
Envisioning opportunities
Future workshop
Preliminary field visit
Focus groups
Photo study
Simulations of future environments
Brainstorming
System scoping
Participatory workshops
Field observations and ethnography
Consult stakeholders
Context of use analysis
28. Planning
• Plan – how to achieve and maintain usability throughout the life of the
system.
• Plan – how to provide required specialist skills.
„If you fail to plan, you are planning to fail”
― Benjamin Franklin
29. Understanding needs
• Best practices
• Context of use
• Stakeholders and users.
• The environment.
• The location and workplace
equipment.
• Tasks
• Tasks and work system.
• Usability needs
• Required system usability.
• Design options
• Design options.
• User-centered solutions.
Context of use
Tasks
Usability
needs
Design
options
30. Understanding needs
Context of use
Stakeholder identification
Field observations
Participatory workshops
Work context
Context of use analysis
Tasks
Task analysis
Work context analysis
Usability needs
Usability benchmarking
Competitor analysis
Heuristic/expert evaluation
Design options
Early prototyping
Usability evaluation
Develop simulations
Parallel design
33. Understanding needs
Visibility of system status
Match between system and the real world
User control and freedom
Consistency and standards
Error prevention
Recognition rather than recall
Flexibility and efficiency of use
Aesthetic and minimalist design
Help users recognize, diagnose, and recover from errors
Help and documentation
34. Requirements
• Best practices
• Context requirements
• Implications of the context of use.
• User requirements
• Statement of user requirements.
• Measurable criteria for the system.
Context requirements
User
requirements
35. Requirements
Context requirements
Define the intended context of use
including boundaries
User requirements
Scenarios
Personas
Storyboards
User interface requirements
Prioritize requirements
36. Analyze requirements
• Best practices
• How usability criteria and requirements can be met by the proposed design?
• Analyze the user requirements.
• Present requirements to stakeholders for use in the development and operation of the
system.
41. Design/development
Don’t make me think.
It doesn’t matter how many times I have to click, as
long as each click is a mindless, unambiguous
choice.
Get rid of half the words on each page, then get rid
of half of what is left.
42. Failed at first?
Don’t worry.
“No matter how thoroughly you plan, no matter how much you think you know, you've
never thought of everything.”
― John Flanagan