As medical device companies strive to make their products more user-friendly, it becomes clear that listening to the end user is an important part of the process. Through small-scale studies and human factor analysis, inhalers can be developed that are simple and easy to use.

1. 8
Thinking Human
As medical device companies strive to make their products more user-friendly,
it becomes clear that listening to the end user is an important part of the process.
Through small-scale studies and human factor analysis, inhalers can be developed
that are simple and easy to use
Inhalation Technology Supplement Inhaler Design
Setting up for a formative HF study with an unseen observer
Julian Dixon at Team Consulting
Two main challenges with human
factors (HF) stand out at the moment:
one is that it has become a ‘hot
topic’ that people do not want to
hear about anymore; the other is
that it is perhaps not clear what the
lasting and valuable contribution
of it will be. However, it can have
real benefits in the development
of inhalers. It is important to look at
the HF perspective and how it might
contribute to future advancements
in both medical devices
and technology.
Innovative Inhalers
It is not helpful for HF to be possessive,
or seek to claim ownership of any
particular aspect of the development of
inhalers or their life in the world. This
perspective is just one voice among
many, and countless progressions
in inhalers occurred before HF were
identified as an integral part of the
design process. There are three aspects
of the inhaler-user relationship where
the industry looks to improve:
1. Designing inhalers that are
easier to use
2. Improving user competence
3. Supporting disease management
Designing Easy-to-Use Inhalers
This topic includes considering the
physical expectations of users, as
well as the cognitive and emotional
demands and a use-related risk
profile. Easy-to-use inhalers can
also enhance the fit with the user’s
lifestyle. Improvements can be
achieved through device design,
but also through drug formulation;
a large number of innovations have
delivered such benefits. Examples
include: GlaxoSmithKline’s Haleraid®
,
Images:©TeamConsulting

2. 9
Inhalation Technology Supplement
Small-scale observational studies use skilled moderators
a simple add-on that enables those
with weakened hands to use a
pressurised metered dose inhaler
more easily; Aptar Pharma’s Prohaler®
,
which was the first dry powder
inhaler (DPI) with the minimal
‘open, breathe, close’ interaction;
and ELPEN’s Elpenhaler®
, a manually
loaded, blister-based DPI, promising
better drug protection and simplified
handling compared with much more
common capsule-based devices.
Improving User Competence
Covering technique training, this is led
by instructional materials, devices and
aids as well as competence monitoring
tools. One model is called ‘Trainhaler
with Flo-Tone’, a ‘dummy’ device in
which one noise is heard when the
canister is pressed down and another
when it is inhaled, thereby helping
users to learn to coordinate their hands
and lungs for optimal drug delivery.
Disease Management Support
Tools and behaviour-changing
interventions – such as reminders,
self-monitoring charts and software,
educational interventions and
gamification – are provided by this,
and they all support and/or promote
adherence to dosing regimens.
One less well-known example of a
product targeting this, created just
over 20 years ago, is Click Health.
They released an educational video
game titled ‘Packy Marlon’, which
was placed in hospitals for children
to play after they had been admitted
after an asthma attack, teaching them
about the condition.
The point is, these innovation
objectives had all been identified
and engaged with before any focused
involvement with HF engineering
(HFE). They are objectives that the HF
would prioritise, of course, but they
cannot really be considered unique
or significant contributions of the
perspective on the endeavour of
inhaler innovation.
What, then, is the unique, significant
contribution of the HF perspective?
To answer this, we must first clarify
what the ‘HF perspective’ is.
The HF Perspective
According to the International
Ergonomics Association, “ergonomics
(or human factors) is the scientific
It is important to look at the HF perspective and how it
might contribute to future advancements in both medical devices
and technology

3. 10
Inhalation Technology Supplement Inhaler Design
discipline concerned with the
understanding of interactions
among humans and other elements
of a system”.
HF is evidence-based and scientific,
a ‘psychology-like’ science. It examines
the interaction between people and
technology, understanding both the
human and the engineering aspects of
a system, as well as the user interface
that sits between them. It is about
acknowledging the human, including
weaknesses or failings, as part of the
system and not as an annoyance. The
HF perspective is realistic with regard
to human capabilities and limitations.
But why is this important when
developing inhalers?
Engineers and others producing a
device can – too readily and without
malice – carry in their heads an image
of a perfectly rational, robotic user.
One who understands and obeys the
rules and will do what the engineers
themselves, with their immense
knowledge of their device, would do.
This tendency to hold an unrealistic
idea of our end users is one of the
human qualities shared by all of us
involved in device creation.
The HF perspective is the antidote to
this tendency. As it includes the human
and their behaviour in the system, it
engages with what is actually going
to happen when people use inhalers.
It is the evidence-based inclusion
of the HF in device development:
we are actively seeking to confront
our designs and changes with the
complication of the user.
Furthermore, the HF perspective
has the goal of maximising real
world performance. It is common
for technical experts to be motivated
by the challenge of improving the
fundamental technical performance
of the systems they develop.
How well can this system operate
when used as intended?
But there is potential here for the best
to be the enemy of good. By including
the human in our understanding of the
system we are seeking to optimise, it
will focus attention on performance in
practice. HF perspectives promote the
argument that it is better to achieve
a large population using a system
well enough, than to have a small
population employing it perfectly.
It encourages the development of
technologies that are robust and
insensitive to user behaviour as
far as they can. This emphasis on
mass achievement of ‘good enough’
is particularly valuable when
designing instructional materials.
The HF concentrates on the impact
on real world performance, not on
the accuracy or precision of each
instructional statement.
Usability Objectives
When talking about HF objectives, we
are really considering another voice
among multiple perspectives. It is
not that the HF perspective stands in
opposition to others – it is alongside
them. By doing so, it may trigger
different design and development
trade-offs and decisions.
Consulting firms are often asked to
test the instructions for use (IFU)
provided with an inhaler. An HF
perspective, with its focus on the
naïveté of real users, highlights
the importance of making the most
fundamental of all messages clear:
the patient should use the inhaler
to breathe in a fine mist of medicine
into their lungs. This message is
often absent from IFUs.
Another example is the common
selection of capsule-based DPIs
by companies developing novel,
orally-inhaled drug products.
Capsule inhalers have some great
qualities, not least that they are
well-established technologies and
can accelerate time to clinic. The
HF perspective into the selection
decision taken early in development
would be to highlight that there
are alternatives to capsules that
may offer a different trade-off of
usability, performance and time
to clinic. Individual foil blisters
provide obvious advantages as
well as improved drug protection
over capsules. The HF perspective
places weight on the handling of
the final system in decisions that
have previously been driven by
technical performance and time to
clinic considerations. By doing so,
it illustrates that one device – the
manual-load blister inhaler – might
just be a Cinderella, never invited
to the ball.
Methods and Studies
HF is not about just conducting studies
– it is also about thinking in structured,
analytical ways about interactions
between people and devices. There are
two methods: analytical and empirical.
The former approach is immensely
valuable and yet has perhaps been
undervalued and underused in the
drug delivery development space. It
includes task, state space and principal
component analyses. Empirical means
comprise practical assessments that
do not involve real users – like bench
testing, for example. However, the
most common method, and the one
currently having the greatest
immediate impact on development,
is the small-scale, qualitative,
simulated use observational study.
The Qualitative Study
One challenge that HF faces in the
drug delivery industry is that the
research devices used are unfamiliar
HF perspectives promote the argument that it is better to
achieve a large population using a system well enough, than to
have a small population employing it perfectly

4. Inhalation Technology Supplement
11
Julian Dixon
is Director of
HF at Team
Consulting,
the leading
medical
device
development consultancy based
in Cambridge, UK. He takes an
active role in understanding
emerging FDA expectations
and practices with regard to
HF, particularly as they apply
to combination products.
Predominantly in the respiratory
and parenteral sectors, Julian has
worked on a large number of drug
delivery device development
projects and has fulfilled a range
of consultancy roles for clients
including HF, facilitation, decision
support and technical
problem solving.
Email: julian.dixon@
team-consulting.com
and counter-cultural to many working
in pharma. The HF is a ‘psychology-
like’ science. Once we include the
human in the system, the variations
we see are too great to allow carefully
controlled, repeatable experiments –
and close control over our participants
is one of the things that we would like
to exclude from our studies. If trials
are too regulated, fewer errors will
be found and thus we will be able to
identify as many improvements.
Our understanding of the difficulties
that real users may face with a system
and its user interface will grow less
quickly if we restrict their freedom to
interact with prototypes.
Furthermore, HF studies are usually
conducted on an extremely small
scale and do not provide statistically
justified, quantitative conclusions –
instead, they are essentially qualitative.
They enquire into the challenges that
people have interacting with systems
and seek to understand the root of
each error. As a result, they identify
how changes to systems and user
interfaces could reduce faults. As they
are led iteratively, there is opportunity
to confirm or disprove an early ‘theory’
of the cause of a glitch. Within a
development programme, holding
many small-scale HF studies is typically
more valuable than conducting a
smaller number of bigger ones.
The key to the value of these small
observational trials is the skill of
the moderator. They are there to
understand, without influencing, what
happened with the participant. Each
partaker is different but patterns
emerge very quickly. We are sensitive
to ‘even a whiff of an error’. Sensitivity
is qualitative too, not statistical.
Conducted with care, this simple
method of putting realistic simulations
in the hands of users is very powerful.
These studies – carried out as part of
an iterative design test process – are
labelled by those engaged in HF as
‘formative’, but this tag has become
mundane and has lost its meaning.
It is worth reflecting that when
referring to ‘formative experience’
in our development – for instance,
as a child or young adult, or early
in our careers – we mean one
with a significant influence on our
subsequent development. HF need
to reclaim the everyday sense of the
word ‘formative’ for the work we
conduct. It really should be formative.
Future Innovation
Historically, identifying targets for
development in inhalers is not the
biggest challenge facing our industry.
Nonetheless, the HF voice will highlight
the promise of certain opportunities
and will weight some benefits
differently than other perspectives.
HF will contribute most significantly
through its impact during innovation.
It provides a mindset and toolkit that
will support the delivery against the
potential of each evolution. Small-
scale, formative studies will play a
key role in ensuring that our realities
match our aspirations.
My experience is that the HF mindset
is, indeed, novel; it makes a different
contribution to both clinical and market
research mindsets, for example. No
single perspective is sufficient to guide
an inhaler development – HF, design
and engineering viewpoints are all
necessary. The joy is, as it should be,
in collaboration.