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Human factors, usability studies and validation testing. Where do you start? How do you approach it? Ann Blandford Professor of Human Computer Interaction New technologies and changing expectations create new opportunities New

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Human factors, usability studies and validation testing.

Where do you start? How do you approach it?

Ann Blandford

Professor of Human–Computer Interaction

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New technologies and changing expectations create new opportunities

  • New technologies create new possibilities.

– New technologies for telehealth and new models of shared care – Networks of devices support data integration – Quantities of health and social data offer potential for new understanding

  • Miniaturisation makes more products feasible and

affordable

– E.g. portable breathalyser kits and vital signs monitoring equipment

  • Changing culture:

“No decision about me without me”

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It all looks so easy if you developed it…

3 Video from UHN Toronto

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Interactive healthcare technologies are not all fit for purpose

  • They need to work reliably

– Hardware and software

  • “If the user can‟t use it, it doesn‟t work”

– Basic usability

  • If the user doesn‟t use it, it doesn‟t work

– E.g. medication reminder apps

  • If the user uses it “off label”, this introduces

vulnerabilities into the system

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Example: out and about with people taking

  • ral contraceptives

Work with Kathy Stawarz

  • What are the extent and causes of unintentional

medication non-adherence?

– Focus initially on oral contraceptives, and forgetting

  • Can technology help?
  • Methods:

– Review of existing medication reminder apps – Online survey

http://www.flickr.com/photos/marklincoln/5255361533/

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Study I: Smartphone apps review

Classified and analysed the functionality of 229 smartphone medication reminder apps

  • 123 iPhone apps
  • 106 Android apps

25 dedicated contraception reminder apps

  • Finding: focus is on just-in-time reminders
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Study II: Online survey

Women taking oral contraception

  • N=1,083
  • 75% age 18-25 years old

http://www.flickr.com/photos/ambersphoto/2067610356/

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Study II: Online survey

What do you use to help you remember to take your pills on time?

N=1,083

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Study II: Online survey

N=1,083

Last week Last month 10 20 30 40 50 60 70 80 Completely forgot at least once Took late at least

  • nce

10 20 30 40 50 60 70 80 90 forgot took late Forgot Took late Last week Last month Use (N=260) Don't use (N=823) 10 20 30 40 50 60 70 80 90 forgot took late Forgot Took late Last week Last month Routine (N=644) No routine (N=439)

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Discussion

  • Current technology focuses on just-in-time

reminders

  • Technology doesn‟t support routines
  • People rely on routines
  • People do not use the apps
  • Technology not fit for purpose?
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A classic software development lifecycle

Source: http://en.wikibooks.org/wik i/Introduction_to_Software _Engineering/Process/Life _Cycle

11 What are people‟s current practices and future needs/options? What design solutions address those needs? Does the proposed design solution still address the needs? Does the implemented system work as envisioned? How have needs and practices changed post-implementation?

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Understanding current practices and needs

  • To design the future, you need to understand the

present

  • Methods for understanding the present include:

– Reference to existing resources (systems, manuals, protocols, descriptions of how people live their lives) – Interviews / focus groups / surveys – Observation of work / life – Contextual Inquiry

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Contextual Inquiry in a nutshell

  • Context: Takes place in the context of use
  • Ongoing Experience: Involves observation and

questioning

  • Concrete data: Focus on real artefacts and events
  • Partnership: Data gatherer works with user on

understanding their work / life

– Recognises that they are experts in this

  • See Beyer & Holtzblatt (1998) “Contextual Design”, or
  • ther texts by same authors

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Identifying possible design solutions

  • Inherently creative
  • Pure intuition can work

– You‟re designing for yourself – How typical of the intended user population are you?

  • Strategies include:

– Use of personas and scenarios – Sketching and prototyping – Use of storyboards – Drawing on design patterns / analogous solutions

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Personas

  • A persona is a rich (evidence-based) description of a

typical user of the intended system

  • The two temptations for developers envisioning users are:

– The users are just like me. They know as much as I do about my design, so it will be obvious to them how it works. – The users are exploring the system to see what is possible with it, and need little knowledge to do that.

  • Personas provide a „tool for

thinking‟ that encapsulate features of Real Users.

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Scenarios

  • Focus on user activity and motivations, rather than system

functions

– Similar to but not the same as use cases.

  • Scenarios are

“informal narrative descriptions” of human activities and tasks that illustrate how systems support work.

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Sketches and prototypes

  • A prototype is a representation of some aspects of

design that helps with idea-generation, communication and evaluation. E.g.

– Cardboard physical mock-up – Paper sketches of screens – Complex demonstrator software

15:27

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Checking proposed solutions against needs

  • Formative testing of prototypes. Approaches

include:

– Expert review – Laboratory / simlab testing with users – Think-aloud testing with users

  • Involves iteration
  • For medical devices seeking regulatory approval, may also

involve clinical trial or other pre-market approval processes

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Expert review

  • Expert review of an early prototype or

implemented system involves…

– Defining some user tasks (typical and edge-case) – Walking through the system interaction systematically looking for usability issues – E.g. Heuristic Evaluation

  • Jakob Nielsen: www.nngroup.com
  • Expert review typically assesses usability, not utility

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User testing of implemented system

  • Approaches include:

– Formal user testing – Post-market surveillance – User feedback – Observations / interviews of practice

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Testing with users

  • User testing involves working with representative

users of a system to identify areas of difficulty with a system

– Usually relatively late in development process – Tasks may be defined by analyst or user – Setting may be more or less realistic – Measures may be quantitative

  • E.g. time to complete task; number of errors

– …or qualitative

  • E.g. user difficulties or perceptions

– May involve user diaries for „home‟ systems

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New designs create new

  • pportunities for use
  • There is a co-evolution between design and use

– Some new uses may be positively regarded – Others (workarounds, violations) expose design limitations

  • Methods for understanding evolved practices

include:

– Interviews – Observations – Contextual Inquiry

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So you know what the problems are…

  • Prioritise them:

– How easy to fix? – How critical / beneficial? – In the current development cycle or the next one?

  • But also make sure you really understand user

requirements, values and practices

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Example: weight management through iCrave

Work with Anne Hsu

  • Started with an interview study to find out people‟s

challenges and motivations for weight management

  • Focused in on one challenge that people reported:
  • vercoming cravings

– Exploited and tested theory about mental imagery

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iCrave: the prototype

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iCrave: the outcome

  • f user testing
  • Found to be easy to use
  • In a one-week user test, it was found to reduce

unhealthy snacking (according to self-report)

  • Appears to have helped foster longer-term change

in attitudes to unhealthy snacking

  • Need longer-term testing… and don‟t assume that

“one size fits all”

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To design the future, you need to understand the present

  • Revolutions in use are rare, and are generally just fast

evolutions!

  • Innovation is essential, but needs to be shaped by an

understanding of people‟s needs and practices

  • There are many resources to support user-centred design
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More on situated studies in healthcare

  • Volume 1 now available: Fieldwork for

Healthcare: Case Studies Investigating Human Factors in Computing Systems

  • Volume 2 (on strategies for conducting field

studies in healthcare) coming soon…

  • Encyclopaedia article on doing qualitative studies:

http://www.interaction- design.org/encyclopedia/semi- structured_qualitative_studies.html

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References

  • Hsu, A. & Blandford, A. (2014) Designing for Psychological

Change: Individuals‟ Reward and Cost Valuations in Weight Management. Journal of Medical Internet

  • Research. 16.6:e138. http://www.jmir.org/2014/6/e138/
  • Hsu, A., Yang, J., Yilmaz, Y., Haque, M. S., Can, C. &

Blandford, A. (2014) Applying Decision Theory To Persuasive Design: Psychological Rewards And Costs In Weight Management in Proc. CHI'14. 3403-3412.

  • Stawarz, K., Cox, A. L., & Blandford, A. (2014). Don't

forget your pill!: designing effective medication reminder apps that support users' daily routines. In Proc. CHI’14. 2269-2278.

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Thank you! Questions?

A.Blandford@ucl.ac.uk http://www.chi-med.ac.uk