Medical Device
Product Development
Insight
Design &
Manufacturing
FDA Registered
ISO 13485:2003
Certified
manager in Abbott Laboratories’s quality and regulatory group, says, “
Guidelines are suggestions for good design
that are not absolute and, therefore,
are not rigid requirements. They give
one of many ways to design, but in the
case of design principles from HE75,
the guidelines reflect expert opinions
that are commonly backed up by references to the research literature. [The
HFE committee] tried to indicate when
product-specific limitations might lead
to other design alternatives.” He clari-fies, “HE75 gives guidelines that, if
followed, will make product approval
easier. However, the user interface design still requires validation through the
methods described in HE74—the HFE
process standard.”
In contrast to best-selling novels,
AAMI HE75 is hardly a page-turner,
and there is little point in reading it
cover to cover. Rather, the authors intended for users to jump directly to
sections of interest. Therefore, for coherence sake, the 25 sections overlap.
Hopefully, the industry vetting and
AAMI editing process will eliminate
any contradictory guidance by the time
it is published. Although the new standard will be available in printed form,
the electronic (PDF) version is likely
to be most useful, enabling users to
search for key words, such as handle,
vibration, or legibility. AAMI typically
sells standards of AAMI HE75’s size
for several hundred dollars, but it has
yet to announce a price.
Target Audience
The new standard’s prime audience is
engineers and software developers who
have a hand in shaping a medical device’s user interface. It gives them a primary information source to support the
design and specification of components
such as handles, controls, displays, and
computer screens. Industrial designers
responsible for shaping and styling a
product should also find the guidelines
useful. Israelski says, “Many developers
can read the design principles and apply
them without being human factors experts. FDA has suggested that developers should be trained in HF to carry out
the HF process, which is still required.”
Early in the design conceptualization
process, product planners including
marketers and the aforementioned en-
gineers can review sections of AAMI
HE75 to determine which guidelines
would make suitable user requirements,
or what FDA calls design inputs.
Of course, human factors engineers
playing a user interface design and
evaluation role on development projects can also draw heavily on the document, which essentially standardizes
the design characteristics that they
have championed for years without
the support of such formalized and
comprehensive guidelines. Who else
might find the new standard useful?
Certainly, risk managers will find valuable information that will help them
judge a new device’s vulnerability to
use error. For example, a risk manager might ask the question, “Does our
portable device have good handles, or
is someone going to injure themselves
or others by dropping it?” Turning to
AAMI HE75, the risk manager would
find the following guidelines:
• Handle grips should be made of
a nonslip material.
• Handle grips should be relatively
conspicuous to encourage proper
handling.
• Handle grips should be visually
distinct from controls and other
elements.
• Handle shape should allow the
user to maintain a neutral or natural and comfortable wrist position
to reduce strain during transport.
• Handles will be used by either
bare or gloved hands that may be
covered with substances common
to medical environments such as
an antiseptic solution, blood, or
talcum powder.
• Carrying handles should distribute weight evenly across the hand,
including the palm, to prevent
pinching from corners or edges.
• The handle size should be large
enough to allow for a hand-to-hand exchange between users.
Such guidelines should help risk
managers perform the necessary analysis to determine whether a design is
vulnerable to use error and thus requires modification. Please note that
sample guidelines such as those presented here are subject to change based
on the AAMI HFE committee’s review
