User Centered Design: Writing Personas, Journey Mapping, and Conducting User Interviews (WIP)


This lesson will cover the foundations of user-centered design as it applies to medical user interface design. User-centered design is the iterative design process focusing on the end-users experience. This lesson is inspired by usability experts in UX research, and medical device manufacturing. You will learn to apply usability techniques from each area of expertise into your work at Innolitics.

Learning Material

At Innolitics we deploy a variety of user-centered design principles as we ideate, develop, and iterate over our products. These include:

Writing personas
Journey mapping
Usability testing

Before completing this lesson:

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Exercise 1

What are 3 methodologies for user-centered design. Are any required by the FDA?

  • Writing personas
  • Journey mapping
  • Usability tests
  • Failure Mode and Effects Analysis (uFEMA)
  • Validation testing (Required by FDA)

Exercise 2

Why are user personas useful, according to the Nielsen Norman Group?


Refer to: Personas Make Users Memorable for Product Team Members

  • Writing the persona helps us understand our users behaviors, attitudes, needs, and goals.
  • It aligns a team of developers to the concept of the end user.
  • It focuses our design on the needs of a specific target user, instead of designing for everyone.
  • It makes the end-user easier to remember during development.

Exercise 3

What are the common elements of a persona?


Refer to: Personas Make Users Memorable for Product Team Members

  • According to Nielsen Norman Group, the essential pieces of a persona are:
    • Name, age, gender, and a photo
    • Tag line describing what they do in “real life”
    • Experience level in the area of your product or service
    • Context for how they would interact with your product
    • Goals and concerns when they perform relevant tasks
    • Quotes to sum up the persona’s attitude

Exercise 4

According to Nielsen Norman Group, what are the three types of personas? Write down a pro and con for each.


Refer to: Persona Types, from Nielsen Norman Group.

  • Proto-personas
    • Pro: They make implicit assumptions about your users explicit
    • Pro: Align assumptions about typical users
    • Pro: Small time commitment
    • Pro: Gateway to future research
    • Con: Less accurate (not data-driven)
    • Con: Less useful for actionable insight - can cause teams to be dubious of their usefulness
  • Qualitative Personas
    • Pro: Small time commitment
    • Pro: Data can be gathered in parallel with other work
    • Pro: More accurate than speculation (data-driven)
    • Pro: Includes key insights that are impossible to derive from analytic data
    • Con: No way to determine the proportion of your user population that each persona represents
    • Con: Possibility to over-represent outliers
    • Con: Organizations with low UX maturity may need to constantly push back on claims that qualitative personas are “not scientific.”
  • Statistical Personas
    • Pro: Less likely to over-represent outliers
    • Pro: Understand user demographics
    • Pro: You can use research findings to improve the design of research (remove survey bias)
    • Con: Expensive
    • Con: Time-consuming
    • Con: Requires expertise in statistical analysis
      As stated by the NNGroup, this method can be “like cracking a walnut using a hydraulic press.”

Exercise 5

What are 3 resources you could utilize to gather data for writing a persona.

  • LinkedIn
  • Job postings
  • User interviews
  • Google analytics
  • Demographic information

Exercise 6

Practice writing a proto-persona for a project you have worked on using data-driven insights.


TODO: Add example

Exercise 7

According to the Nielsen Norman Group what are 3 points where personas fail.


Refer to: this Video and this Article

  • Lack of understanding
  • Inaccurate expectations
  • Uncertainty about how they can be used
  • Often created and imposed
  • No buy-in from leadership
  • Created in a silo
  • There is a flaw in the data (or no data was used)

Exercise 8

According to Nielsen Norman Group, what is a journey map, and what purpose(s) does it serve?


Refer to: Customer Journey Mapping
A journey map is a visualization of a product the includes a user goals, actions, thoughts and emotions when using a product.

Some purposes a journey map can serve include:

  • Shift a company’s perspective from inside-out to outside-in
  • Break down silos to create one shared, organization-wide vision
  • Assign ownership of key touch-points to internal departments
  • Target specific customers
  • Understand quantitative data

Exercise 9

According to Nielsen Norman Group, what are the key elements of a journey map?


Refer to: Journey Mapping 101

  • Section 1
    • Actor
    • Scenario + Expectations
  • Section 2
    • Journey Phases
    • Actions, Mindsets, and Emotions
  • Sections 3
    • Opportunities
    • Insights and ownership

Exercise 10

Practice creating a journey map for one project where you think it could provide useful insight. If you worked on this project with a team, explain your journey map to another colleague and note any incongruities you had about the user journey.

  • TODO: Add example

Exercise 11

Based on what you have read, why is user testing important? Give an example of biases you might have as a product developer that would influence your assumptions of user behavior.


Refer to: User Testing Video by Jakob Nielson, User Centered Design, Reducing Medical Device Risk with Usability Testing, and the FDA’s usability guidelines

  • Nielsen Norman Group:
    • You are not the user
    • It’s a cheap solution to improving products
    • It is convincing to stakeholders
  • Adobe:
    • “People ignore design that ignores people” - Frank Chimero
    • Creates likable products
    • Unifies teams on product expectations
  • FDA:
    • Ensure that device UI does not cause harm or degrade medical treatment
    • Many use errors cannot be anticipated until device use is simulated and observed
  • Bressler Group:
    • It can prevent life-threatening medical device errors
    • It can prevent product recalls
    • It can help you get your product to market
  • Example bias
    • “I know how to search the words on a web page with (cmd + f), therefore I may assume users would not benefit from a page search feature.”

Exercise 12

What is user-testing? How does it differ from a user interview?

  • Usability testing is the popular UX research methodology where a facilitator asks a participant to perform tasks using one or more user interfaces. The goal of this process is to gain insight on the participant’s behavior and listen for feedback about the interface design.
    Refer to: Usability Testing 101
  • A usability test is different than a user interview because the test uses specific tasks to gain user insight, whereas an interview asks for user feedback about their overall experience with the product.
    Refer to: User Interviews

Exercise 13

Read this article from Nielsen Norman Group. Write three tasks you would ask in a usability interview for an internal project at Innolitics, or a relevant competitor. Use this format to construct the tasks:

Example from the MAUDE-Alert usability tests

Goal: Identification of Known Use-Related Problems relating to devices that are similar to the one under development.
Task: Identify known use related problems that have occurred to devices that are similar to a Suture Kit.
Consequence: Users may produce a product malfunctions that could be prevented.

Exercise 14

Refer to the Nielsen Norman Group for resources on how to conduct usability tests:
Conduct a 15-30 minute usability test with a colleague. The articles below are resources that have helped us conduct usability testing in the past. We recommend reading them before conducting your interview.

Exercise 15

Read this article about interpreting usability tests. Write a quick findings report for your usability test.

  • TODO: Add example

Exercise 16

What are the pros and cons of quick findings usability reports vs. formal reports?

  • Quick findings:
    • Pro: Fast to write
    • Pro: More likely to be read
    • Con: Do not withstand time
  • Formal reports:
    • Pro: Archival
    • Pro: Give more accurate results
    • Con: Take lots of time
    • Con: Can be burdensome to review

Exercise 17

If you were told to build a new internal web app or open-source project (e.g. DICOM Standard Browser, MAUDE-Alert, etc.), and you had 1 week to present the first iteration of the design what methods of user-centered deign would you use and why?


Building a successful project from scratch requires user research. Determining the appropriate research methodologies is influenced by the time, resources, and purpose of the product. Because the product at hand needs to be designed in 1 week, it is important to consider brief user research methods that will provide actionable insight into your design. Some methodologies you might consider are:

  • Write 2-5 proto-personas
  • Conduct a brief competitor analysis
  • Sketch a journey map, and use the visualized experience as the baseline for the design

Exercise 18

What are some of the challenges that arise when there are several stakeholders in the product (product owners, developers, marketers, investors)?

  • Clients with a naive background in software development may not believe in the effectiveness of user research
  • Clients may not have the time to conduct user research
  • Stakeholders may completely disagree with the outcome of a user-centered design
    Refer to: How to Collaborate with Stakeholders in UX Research

Exercise 19

When designing user interfaces for medical devices, can you think of any risk factors that come with poor usability? Write two risk factors and give an example of how each could be mitigated.

  • TODO

Exercise 20

In your opinion, what are your responsibilities as a developer to ensure a client product avoids usability error?


There is no right answer to this, but here are some things to think about:

  • Our website states we know: “Medical user interface design, human-factors engineering, and IEC62366-1”. Does this imply we have a duty to inform clients of usability risk factors in their product?
  • Noting that poor usability research can lead to maladaptive changes in design, what level of competence is required to ethically provide usability consulting?
  • If investors disagree with our usability recommendations, who should we prioritize? The users or the investor?

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