Corinna Proctor Joins Human Factors MD

Corrina Proctor

Human Factors MD is pleased to announce that Corinna Proctor has joined the company as a Senior Consultant. Corinna has nearly 20 years of experience employed in the field of Human Factors. She has worked in a variety of domains including medical hardware, health IT, and consumer / commercial IT product development. She has expertise in gathering user requirements and testing pre-market designs of hardware and software user interfaces. She has experience working with a variety of medical device categories as well as Health IT Electronic Health Record (EHR) testing and reporting. She is experienced in applying User-Centered Design activities into product development processes, as well as applying the requirements of IEC 62366-1, HE75, and various FDA Guidances to support the development of safe and effective medical products. Corinna holds a Master’s Degree in Cognitive Psychology from North Carolina State University.


Drug Delivery Human Factors Workshop

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Christina Costanzo Mendat, PhD will be leading a workshop at the Drug Delivery Partnerships conference on January 22, 2018 in Palm Beach Gardens, Florida.

This 30-minute workshop, Using an Integrated HF Approach to Design and Validation, will focus on explaining how to effectively integrate human factors into the product development and risk management activities of combination products.

To learn more about the conference, visit the following link.


Liz Mauer Joins Human Factors MD

Liz Mauer

Human Factors MD is pleased to announce that Liz Mauer has joined the company as a Senior Consultant. Liz has over 15 years of diverse experience in human factors research, design, and testing. She has particular expertise in planning, conducting, and analyzing findings from user research studies and translating those findings into directions for useful, usable, and desirable products. She is also experienced in applying the requirements of IEC 62366, HE75, and various FDA Guidance documents to support the development of safe and effective medical products. Liz holds a Masters Degree in Human-Computer Interaction from Carnegie Mellon University.


Human Factors for Injectables Workshop

PFS & Injectables Summit 2017

Tim Reeves, PhD CHFP and Christina Costanzo Mendat, PhD will be leading a Pre-Conference Workshop at the 7th Edition PFS & Injectables Summit 2017 on September 26th in San Diego, California.

This three hour workshop, Avoiding Pitfalls & Optimizing Human Factors for Prefilled Syringes & Autoinjectors, will leverage Tim and Christina’s decades of combined experience helping clients create safe, effective, usable, and innovative combination products.  

Participants will be encouraged to evaluate injectable devices from a human factors perspective. The workshop will cover:

  • Common use-related pitfalls with injectable combination products
  • Why these same issues continue to occur
  • How a human factors oriented use specification can guide the design of novel injectors or the selection of off-the-shelf devices

Much of the workshop is interactive. Participants will work in “product teams” to define a use specification for a possible combination product. With Tim and Christina’s guidance, teams will explore how to utilize a use specification to guide the design of an injection device, or as an aid for choosing an off-the-shelf device for use with their products.  


Safety Information Components

by Eric F Shaver, PhD

This is the second in a multipart series on the design, presentation, and evaluation of safety information (warnings, precautions, and contraindications) in device labeling.

The research literature on safety information, specifically warnings, identifies four components (signal word, identification of the hazard, information on how to avoid the hazard, and consequences for failing to avoid the hazard) that typically are included when being developed.

Signal Word (and/or Safety Alert Symbol)

According to ANSI Z535.6 (2011), there are three signal words that can be used to identify safety information that addresses potentially hazardous situations that might negatively impact users. These signal words connote different degrees of hazard severity. They are:

  • DANGER (indicates a hazardous situation which, if not avoided, will result in death or serious injury)
  • WARNING (indicates a hazardous situation which, if not avoided, could result in death or serious injury)
  • CAUTION (indicates a hazardous situation which, if not avoided, could result in minor or moderate injury)

A fourth signal word, NOTICE, should only be used for non-personal injury hazards, like property damage.

Often the signal words DANGER, WARNING, and CAUTION will be paired with a safety alert symbol (see the image below) to increase conspicuity of the safety information. The safety alert symbol should not be used with NOTICE.

Safety Alert Symbol

Identification of the Hazard

Safety information should clearly identify the potential hazard(s) of the product. Doing so provides intended users with information that will help facilitate making an informed decision about how to safely interact with the device.

Information on How to Avoid the Hazard

Safety information should clearly identify what steps should be taken to prevent personal harm from occurring when using the device. Depending on the hazard complexity, this could be brief for simple concepts or require additional explanation for more complex concepts. Moreover, if it is known that potential users of the device have sufficient knowledge about the appropriate actions needed to avoid the hazard, it might not be necessary to include this content in the safety information.

Consequence for Failing to Avoid the Hazard

Safety information should clearly identify the potential consequences for failing to heed the message. Stating the consequence of a specific hazard may not be necessary if it can be readily inferred from the overall message of the safety information.


ANSI Z535.6. (2011). Product safety information in product manuals, instructions, and other collateral materials. Rosslyn, VA: National Electrical Manufacturers Association.


Safety Information in Device Labeling

by Eric F Shaver, PhD

This is the first in a multipart series on the design, presentation, and evaluation of safety information (warnings, precautions, and contraindications) in device labeling.

Companies face mounting pressure to design and develop higher quality device labeling that meets the requirements of users. These pressures originate from several sources. First, over the past decade, regulatory authorities, such as the FDA, have expanded the requirements to demonstrate that users can employ labeling in order to safely and effectively operate medical and drug-delivery devices.

Second, traditional competitors, along with new market entrants, are bringing cutting-edge techniques about designing effective device labeling from other industries to medical and drug-delivery devices.

Lastly, sophisticated users are increasingly expecting device labeling to meet or exceed what they experience with their consumer products.

Each of these developments point to the importance of companies embracing new ways of designing and developing device labeling in order to maximize their success in the pre-market approval process and against their competitors.

One important, but often overlooked, aspect of device labeling is safety information, which includes warnings, precautions, and contraindications. While most companies would readily acknowledge the importance of identifying and clearly communicating the potential hazards associated with their devices, oftentimes they are perplexed about the best methods for accomplishing it.

There is a dearth of actionable resources on how to design, present, and evaluate safety information in device labeling that stakeholders can readily access. This blog post series will address this deficit. Some of the topics that will be covered include:

  • Safety information components
  • Purpose of safety information
  • When safety information is required
  • Challenges developing safety information
  • Why safety information isn’t always effective
  • Questions to ask when developing safety information
  • Design considerations when developing safety information
  • Issues seen in device labeling safety information

I look forward to sharing tips on developing safety information that clearly communicates potential hazards associated with medical and drug-delivery devices to intended users.



Passive Needle Features (Sharps Protection)

by Christina Mendat, PhD

This is the fourth in a six-part series on prefilled syringes where we address some issues we’ve encountered in our multiple client engagements.

An increasing number of prefilled syringes are being developed with a sharps protection feature. An example is depicted in the figure below.  The prefilled syringe is placed into an exterior housing that retracts once the injection has completed. The needle is retracted into the housing and the exterior housing locks into place around the needle. This is a wonderful feature and it is easy to understand its appeal. It provides protection from needle sticks and adds another level of protection once in the sharps container.


There are human factors issues that should be considered with these products, however. They include:

  1. Barrel spinning. With some variations on this design, the syringe barrel can spin within the exterior housing. This can make a few things difficult including a) viewing the syringe graduations, b) setting the orientation of the needle bevel, and c) orienting the flange position while viewing the syringe.
  2. Viewing the Syringe. Oftentimes, laypeople are not aware that they can spin the barrel. They assume the syringe is positioned where it is supposed to be, even if it is difficult to see the information.
  3. Low Dose Volumes. Setting low dose volumes in devices like these can be extremely difficult (and not just for laypeople, but for health care professionals as well). The exterior housing has a cutout that permits users to see through to the syringe barrel. The cutout seldom runs the whole length of the syringe barrel for obvious reasons, and the housing can still obscure some of the syringe barrel. Moreover, the spring can also make it hard to see the barrel and plunger. For medications with very low volume to administer, the housing and spring can make it difficult to see the liquid and can negatively affect a user’s ability to measure a dose accurately.

Tim Reeves Joins AAMI Faculty

Tim Reeves, our Managing Director, will be among the faculty at AAMI’s upcoming Human Factors for Medical Devices course presented in Arlington, Virginia May 2 through 4 and in Dublin, Ireland June 6 through 8.  This three day public course offers participants a comprehensive introduction to human factors as it relates to medical devices. Course faculty include FDA representatives from both the Center for Devices and Radiological Health (CDRH) and the Center for Drug Evaluation and Research (CDER).

For details on both events, visit the Events page on AAMI’s website.  


Eric F. Shaver, PhD Presenting at HFES 2017

2017 Human Factors and Ergonomics in Health Care Symposium

Eric F. Shaver, PhD, Director of Human Factors, will be presenting on March 6th and 7th at the HFES 2017 International Symposium on Human Factors and Ergonomics in Health Care in New Orleans. The two topics he will be covering are:

  • Best Practices of Safety Information Presentation in IFUs [Lecture]
  • Strategies for Successful Human Factors Collaboration with Medical Device Development Teams [Poster]

Also, he will cochair the Ethical Challenges with Usability Testing panel and lecture session for the Medical and Drug-Delivery Devices Track.

We hope that you’ll be able to attend both the lecture and poster.


Human Factors Testing and Clinical Research

By Tim Reeves, PhD CHFP

Montreal, site of the 25th Annual Meeting of the Society of Clinical Research Associates

This month, I had the pleasure of giving an invited presentation at the 25th Annual Meeting of the Society of Clinical Research Associates (SOCRA) in Montreal, Canada.  Over 1,000 people attended the three-day event.

My presentation focused on the role of human factors testing in the development of combination products, and how human factors studies “complement” traditional clinical trials in establishing combination product safety and effectiveness.

Combination products (a drug packaged with its own delivery device) are increasing ubiquitous in healthcare as the costs of providing therapy have pushed the responsibility for administration of many drugs to patients themselves.  But while drug delivery devices designed with patients in mind (such as auto-injectors, inhalers, and transdermal patches) may seem simple to use, usability testing and post-market reports show otherwise.  Even devices that seem simple enough (e.g., a transdermal patch) can be difficult for patients and lay caregivers to use correctly.  Injection devices, inhalers, and transdermal patches have well known and documented usability issues.  When used incorrectly, these combination products have the potential to harm patients or compromise their medical therapy.

In an effort to reduce the risks associated with use-related issues for combination products, the FDA and other regulatory bodies have turned to the discipline of human factors, including human factors testing.

Human factors validations studies differ from clinical trials in many respects.  For example, a typical clinical trial may have a 1,000 participants or more, while a typical human factors study may have 60 or as few as 15.  Clinical trials have statistical endpoints, while human factors studies are qualitative only.  Arguably, the most meaningful difference between a phase 3 clinical and a human factors study is how each deals with potential problems participants may have with the drug delivery device – so called use errors or use-related hazards.  To borrow from the ISO definition, a use error arises whenever anyone uses your device in a way that, as the manufacturer, you hadn’t intended.  Some use errors have the potential to harm the patient or compromise their medical therapy.  Phase 3 trials are tightly controlled, to try and minimize the influence of use errors.  After-all, the focus of a phase 3 trial is on the safety and efficacy of the drug. Is the drug safe at these doses?  To get the cleanest data possible, clinical studies are designed to minimize use errors.  Patients and investigators are highly trained.  Drug administration is monitored and controlled.  Researchers want to minimize the potential for error in how the drug is given so as to minimize dosing errors.

Human factors validation studies are quite different.  For a human factors study, the focus is on use errors.  They are, in experimental design parlance, the dependent variable in a human factors study.  These studies are designed as post-market simulations.  Participants are trained only to the extent that they would be trained when the product is released commercially.  Often this means patients and caregivers are left to learn how to use combination product devices on their own.  Human factors studies put participants in realistic situations, including those where situational factors, such as poor lighting or fatigue might contribute to use errors.  And participants are given use scenarios that reflect what might be expected to happen, in real life.  The goal is to demonstrate that the device is designed such that the risk of use errors, including their potential for harm, have been minimized as much as possible.  A successful human factors study is one in which few if any use errors are observed, and the risk associated with those errors, should they arise in actual use, post market, is as low as possible.

But while human factors studies and clinical studies differ in important ways, they are complementary, as both are required to establish the safety and efficacy of a combination product.  Human factors testing is required to demonstrate that the device component can be used to deliver the drug safely and reliably, and clinical testing is required to establish that the drug component is safe and effective at recommended doses.


AAMI Warnings Webinar


Eric F. Shaver, PhD, Director of Human Factors for Human Factors MD, will be presenting a two-part webinar on Warnings and Safety Information in Device Labeling for the AAMI University Distance Learning program.

Part I will provide a solid foundation on the science of warnings and safety information.  Part II will focus on best practices of warnings and safety information design and presentation in device labeling.

Part I will take place on November 3rd and Part II on November 10th from 11:00 am – 12:30 pm EST. To learn more about the webinar, including how to register, visit the Distance Learning website.


Limitations of Stand-Alone Symbols in Labeling

By Eric F Shaver, PhD

With the publishing of the FDAs Use of Symbols in Labeling final rule earlier this year, many companies are looking to incorporate “stand-alone symbols” (symbols without corresponding explanatory text) in medical devices labeling. This is understandable because symbols have the potential to:

  • increase the salience of labeling,
  • rapidly communicate important information,
  • overcome language barriers, and
  • require less real estate than written communication.

But, symbols aren’t a panacea for all device labeling challenges – especially if they’re not understandable. A recently published article in Packaging Technology and Science by Seo, et al (2016) highlights this important point.

The authors had 86 healthcare providers evaluate 38 symbols from AAMI/ANSI/ISO 15223-1, a consensus standard currently recognized by the FDA. Participants were asked to provide a meaning for each of the symbols. Comprehension was determined by two reviewers evaluating the responses using one of five categories: (1) correct; (2) wrong; (2b) wrong and the response given is the opposite of the intended meaning; (3) the response given is “Don’t know;” and (4) no response is given. The researchers then used an acceptance criteria based on ANSI Z535.3 (85% successful comprehension with less than 5% critical confusions) to determine whether each symbol was “successful” or “unsuccessful.”

The results demonstrated that only six of the thirty-eight symbols tested (Non-Sterile; Contains or Presence of Natural Rubber Latex; Batch Code; Sterile; Catalog Number; and Caution, Consult Accompanying Documents) successfully met the acceptance criteria. Interestingly, five of the six symbols incorporated text in the visual. Moreover, four of the symbols (One-Way Valve; Sample Site; Fluid Path; Liquid Filter with Pore Size) garnered 0% comprehension.

Given this information, what’s a company supposed to do?  While it might be tempting to incorporate stand-alone symbols in the medical device labeling and be done with it, unfortunately, it’s not quite that simple. It’s important to understand whether the intended users of your product will comprehend the intended message of the symbols you plan to incorporate in your labeling. This can be determined by testing with prospective users.  If the symbols under evaluation meet an ANSI Z535.3 type threshold, great.  If not, then you should consider providing corresponding text that reinforces the symbols message in order to maximize comprehension.


AAMI/ANSI/ISO 15223-1: 2007/(R)2012 and A1:2008/(R)2012. Medical devices – Symbols to be used with medical device labels, labeling, and information to be supplied – Part 1: General requirements. Arlington, VA: Association for the Advancement of Medical Instrumentation.

ANSI Z535.3-2011. American national standard criteria for safety symbols. Rosslyn, VA: National Electrical Manufacturers Association.

Seo, D.C., Landoni, M., Brunk, E., Becker, M.W., & Bix, L. (2016).  Do healthcare professionals comprehend standardized symbols present on medical device packaging?: An important factor in the fight over label space. Packaging Technology and Science. Advance online publication. 10.1002/pts.2199.

Use of Symbols in Labeling, 81 Fed. Reg. § 115 (June 15, 2016).


Clinical Consultant Joins Human Factors MD


Human Factors MD is pleased to announce that Angela Hock RN, BS, BSN has joined the company as a Clinical Consultant. Angela has over 18 years experience in healthcare as a registered nurse. She spent 12 of those years as a liaison for an acute rehabilitation and long term acute care hospitals. Her clinical experience includes: cardiology, neurology, orthopedics, trauma, pediatrics, dialysis, oncology, surgery, respiratory, general debility and medically complex patients. She holds a Bachelor of Science in Exercise and Sport Science with a Minor in Gerontology from The Pennsylvania State University. Her degree in Nursing is from Geisinger School of Nursing in Danville, Pennsylvania and a Bachelor of Science in Nursing from The University of North Carolina at Charlotte. Angela provides a wide knowledge base of the extensive healthcare continuum and serves as a clinical consultant for Human Factors MD.


FDA Allows Stand-Alone Symbols on Labeling

By Vince Velocci, MS

As of June 15, the FDA has revised device labeling regulations to allow for “stand-alone symbols” on labels and labeling in general and additionally for the symbol statement “Rx only” on prescription devices.


The industry has asked for and been granted the ability to use stand-alone symbols consistent with those placed on devices in jurisdictions outside the US. The rule will harmonize US requirements with the:

  • European Medical Device Directive (Medical Device Directive 93/42/EEC)
  • International Electrotechnical Commission (IEC 60417)
  • International Organization for Standardization (ISO standard 7000-DB)


Until now, the agency has required symbols to have adjacent English explanatory text (medical devices and IVD for professional use). The change allows symbols developed by SDOs (standards development organizations) to be used as long as:

  • The symbols are used according to specifications for use of symbols, as per FDA section 514, and the SDO is recognized by the agency; and
  • When the symbol is NOT from an SDO or is but is NOT used as per FDA section 514  BUT the manufacturer determines that the symbol is likely to be understood by the “ordinary individual”.

In these cases, the symbol must be explained in a paper or electronic glossary. There must be a conspicuous English statement identifying the location of the glossary.  It should be noted, that for articles distributed in Puerto Rico or other non-English Territory, the predominant language may be used.

In addition, the final rule allows the use of the symbol statement “Rx only” or “℞ only” for labeling of prescription devices.


The agency expects the net cost benefits to be 6.6 to 22.3 million dollars (annualized over 10 years).


CAN I USE NON-APPROVED SYMBOLS?   Sounds like YES, assuming the symbols are recognizable by the target users and are included in a glossary which describes their meaning.

DO DRAWINGS AND PICTOGRAMS FALL UNDER THIS RULE?  Instructions for use and quick reference guides often contain drawings and pictograms. These do not fall under these rules and can be used freely.

With both of these, presumably it is up to the vendor to provide evidence that their symbols and/or their pictograms are recognizable and understood by the target population. The best way to do this is formative testing. So test early and test often!


Auto-Injectors, Nurses, and Mental Models

by Tim Reeves, PhD CHFP

Over the years we have run numerous usability studies with auto-injectors. And while auto-injectors provide significant usability advantages over more traditional syringes, from pre-set dosing to built-in sharps protection, we’ve certainly seen our share of users struggle to use these devices both safely and effectively. Curiously, those who sometimes have the most difficulty are not always who you’d think.

We’ve witnessed nurses have all manner of problems using auto-injectors – failing to remove an auto-injector’s safety release, holding the device at the wrong orientation (exposing themselves to needle sticks), pressing imaginary buttons to trigger activation, and failing to hold auto injectors in place long enough after activation to deliver all of the medication. It’s not unusual to see use error rates among nurses exceed those of untrained lay users.  And unfortunately, it’s not uncommon to have nurses who report training patients on the use of auto-injectors, have difficulties in our studies.

Why would nursing experience make it harder to learn and use an auto-injector correctly?

The answer lies with mental models. Cognitive psychologists use the concept of mental models to explain how we learn about and manage our interactions with objects in the world – from simple devices like auto-injectors, to complex “objects” like people (e.g., we have a mental model of our smartphone and a mental model of cousin Bill). When dealing with something new, we quickly develop a mental model of how it works, and for expediency, we sometimes borrow from existing models that seem reasonably analogous (my new Apple phone seems a lot like my old Blackberry, and my new neighbor seems a lot like cousin Bill).

We use mental models to make sense of the things around us, to understand how things work, and to guide our interactions. But models are by definition abstractions. To the extent that our mental models effectively represent how something works, we do well in our interactions. But if our models are impoverished, or worse, inaccurate, we do poorly.

Why do some nurses have difficulties with auto-injectors? They have poor mental models of how auto-injectors work. It seems likely that these nurses model auto-injectors as analogous to pre-filled syringes, and expect auto-injectors to work much the same way as pre-filled syringes do.

To use a pre-filled syringe, you first remove the needle cover, insert the needle through the patient’s skin, and fully press the plunger to deliver the medication, controlling the flow rate as you go. When the plunger is fully depressed, the medication has been given and the needle is safe to remove.

An EpiPen®, the most ubiquitous example of an auto-injector, doesn’t work this way. And the differences create predictable errors. If you mentally model an EpiPen® as analogous to a pre-filled syringe, you will have difficulties.

Pre-Filled Syringe       EpiPen®
Remove the needle cover. To the extent that nurses treat a needle cover and a safety lock as analogous, they expect the auto-injector needle to come out of the safety end.  Many auto-injectors are not designed that way, including the EpiPen®.
Push the plunger to deliver the medication. We have seen many nurses push imaginary buttons on simple auto-injectors in an effort to initiate dose delivery.
End of push means the medication is delivered. Perhaps the most common use error we’ve seen nurses commit is not holding an auto-injector in place, after activation. These nurses treat resistance after pushing as signifying the end of the injection, much like resistance from a plunger means that all of the medication has been expelled. These nurses don’t wait for the auto-injector to complete delivery.

We’ve also seen nurses commit these same errors, even after reading instructions that are otherwise effective in guiding lay users. We’ve also watched nurses finish failed injections (e.g., not removing the safety and as a result, delivering no drug at all) feeling quite confident they successfully delivered the medication. Unfortunately, with some auto-injector designs, the visual, auditory, and tactile cues are not strong enough to aid these nurses in detecting use problems. The culprit is in part, a confirmation bias that leads us to give inappropriate weighting to feedback that confirms our expectations while ignoring feedback that runs counter to them.  But that’s a topic for another post!


Dear FDA


by Eric F Shaver, PhD

Earlier this month, the Human Factors and Ergonomics Society (HFES) held the 2016 International Symposium on Human Factors and Ergonomics in Health Care: Shaping the Future in San Diego, California.  The event was well attended by researchers, practitioners, industry representatives, and students from around the world with an interest in advancing human factors efforts in the healthcare domain.  

On the closing day, Tim Reeves, PhD CHFP, Managing Director of Human Factors MD, moderated the Dear FDA panel. The idea for the panel was born out of an impromptu discussion at last years symposium. As Tim outlined at the start of the session, five years have past since the FDA published the Draft (and now Final) Guidance. And while the Guidance has been tremendously helpful in improving the safety and effectiveness of medical devices, there are opportunities to enhance the FDA’s approach: to improve the quality and validity of the human factors data we collect and conclusions we draw from human factors studies. Five years of practice is also a sufficiently long time to begin to ask the broader question of whether the FDA should redefine the boundaries of its approach to human factors?

In formulating the panel, Tim challenged panelists with the task of making a case for changing some aspect of the FDA’s current thinking on human factors. The arguments were to be science-based: panelists were asked to provide a solid rationale, based on human factors principles, for their recommendations.

The panel consisted of four human factors experts:

  • Adam Shames, MBA – Founder and CEO of Core HF
  • Eric Bergman, PhD – Director of Human Factors Engineering at Fresenius Medical
  • Shannon Clark, BS – Principal of UserWise
  • Anthony (Tony) Andre, PhD CPE – Owner and Founding Principal of Interface Analysis Associates

Below are key points covered by each panelists:

Adam Shames, MBA

Adam argued that the FDA should expand its focus to incorporate other aspects of user-centered research and design, beyond safety.  While patient and user safety is a necessary objective, other aspects of user experience have the potential to influence user behavior in meaningful ways, including the rate of device adoption and compliance with medical therapies.  Adam argued that broadening the FDA’s focus, beyond safety, would encourage sponsors to develop products that are more apt to meet all patient and user needs.

Eric Bergman, PhD

Eric recommended that the FDA reconsider its definition of “use error” offered in the final Human Factors Guidance. The definition limits “use errors” to use issues with implications for safety, and as such, is inconsistent with the broader definition of use error provided in 62366-1. Eric also asked that the Agency clarify how sponsors should think about “effectiveness” when attempting to validate “safe and effective” use.  Would the Agency approve a device that was safe but not effective?

Shannon Clark, BS

Shannon recommended that the FDA allow sponsors to consider the likelihood of use-related hazards when defining critical tasks and risks. While the Guidance directs sponsors to focus on criticality, as likelihoods are inherently difficult to assess, Shannon made the point that the very concept of “reasonably foreseeable” hazards requires consideration of likelihoods, and accordingly, consideration of  likelihoods is inescapable.  We still need likelihood to determine test cases for validation.

Tony Andre, PhD CPE

Tony raised two issues relating to human factors validation testing. The first is that some products are best validated under more longitudinal use conditions, or after an initial learning phase, rather than during first exposure. The FDA’s focus on initial use may uncover initial challenges when learning to use a device, but doesn’t validate that devices can be used safely once learned.  The second questioned the value in testing untrained users in validation studies without asking them to read the instructions. Tony argued that this use case doesn’t tell us much. How can a study of what happens when people don’t get trained and don’t read instructions be a validation?

The event was attended by approximately fifty people, and included a robust exchange between the panelists and members of audience. Among those in attendance were Irene Chan, the Deputy Director of CDER’s Division of Medication Error Prevention and Analysis (DMEPA), and Xin Feng, from CDRH’s Human Factors Pre-Market Evaluation Team. Both Irene and Xin thanked the panel, welcomed the discussion and offered comments and insights of their own.   


The Plunger Blues

by Christina Mendat, PhD

This is the third in a six-part series on prefilled syringes where we address some issues we’ve encountered in our multiple client engagements.

What’s in a plunger you may ask? A lot more than one may think. A plunger is a plunger right? So, how do you set the dose? Some plungers have a more conical shape whereas others have a flat shape. For laypeople, and even health care professionals, the conical plunger can be quite confusing. Example, what is a conical base? You’d be surprised how many interpretations we’ve heard.


Although prefilled syringes come “prefilled” there are times that variable doses are required. Some of these dose volumes can be extremely low (e.g., .25 – .45mL). To that end, the graduations, label, and plunger-type become extremely critical. Will users be able to find the appropriate setting and if not, how can this be addressed?

In a recent study using a conical shaped plunger, a number of experienced healthcare professionals (physicians and registered nurses) struggled with determining when they had set the dose correctly. Specifically, there was confusion as to how the dose should be read (i.e., at the top of the conical shape or the bottom of the conical shape). There was no consensus on how the dose should be read using the conical shaped plunger. Had a flat shaped plunger been employed, this confusion would likely have been prevented.

If your drug has limited +/- variability, as it relates to drug volume, it may be wise to think hard about the plunger that has been selected and how it will interact with other device features. Most importantly, will users be able to set the intended dose?


Size Does Matter for Syringe Flanges

by Christina Mendat, PhD

This is the second in a six-part series on prefilled syringes where we address some issues we’ve encountered in our multiple client engagements.

Not all flanges are created equally. One place we often don’t see human factors used enough is when selecting a particular off-the-shelf component. A good feature to solicit input from a human factors professional is the flange. The flange is where the user places the fingers in order to carry out an injection.

Syringe Flanges

Some companies have started to develop “extended flanges.” These extended flanges allow larger hands to more readily use the devices. They can truly improve the user experience especially when interacting with highly viscous drug products. Beware of these flanges, however, to make sure they stay on well. We have seen some flanges that, during use, slide off the syringe. If this were to happen during an actual injection, the result could be a painful experience for the patient.

Size DOES matter in this case. Extended flanges are great except when users cannot dispose of them properly. We have also seen examples of flanges that prevent disposal into traditional sharps containers (or take a good bit of manipulation to get them into the container).


On-Syringe Labeling

by Christina Mendat, PhD

Prefilled syringes seem to be taken for granted when it comes to human factors evaluations and testing. However, it has been our experience (working on multiple prefilled syringes) that these combination products have more to them than meets the eye. This is the first of a six-part series on prefilled syringes where we address some issues we’ve encountered in our multiple client engagements.

Oftentimes, the syringe label (also called the device label) is left to the last minute. Certainly, there is a lot more entailed to this small label than some realize. Branding, text size, positioning, manufacturing constraints, etc. the list goes on and on. From a Human Factors perspective, one of the last things companies should do is wait on creating the syringe label. The syringe label can have fairly marked adverse effects on usability if not thought through carefully and included in the development process early on.

Here are a few recent examples we have experienced:

  1. Verifying that the appropriate dose volume is present in the syringe is an essential part of interacting with any prefilled syringe. If the graduations are covered by the syringe label, patients and caregivers are unable to discern readily if the fill volume is correct. Making an assumption could ultimately affect the dose efficacy.
  2. Verifying the dose color is often an essential part of interacting with any prefilled syringe. It is critical to ensure that the labeling itself does not obscure direct visualization of the drug product. For instance, is there color on the label that is seen through the label which results in an “illusory” appearance of color to the drug?
  3. Is the information readily visible? Text size is often overlooked yet is a basic 101 of Human Factors. Most importantly, is the expiration date readily visible? This can be affected by the ultimate layout. A primary culprit of downgraded text size is due to branding and logos. While both branding and logo are undeniably important, it is equally important to ensure that the rest of the label content and format is presented in a way that users can safely and effectively use it.

Real Device Labeling for Real People

by Heather Colbert

On September 29th and 30th, 2015, the FDA hosted a public workshop on “Medical Device Patient Labeling.” The workshop was organized by the Center for Devices and Radiological Health (CDRH) with participation by FDA staffers from the Center for Drug Evaluation and Research (CDER). The purpose of the workshop was to discuss the clarity of the current patient labeling guidelines and gather input for upcoming updates to the existing 2001 “Guidance on Medical Device Patient Labeling.” Attendees included stakeholders representing medical device manufacturers and pharmaceuticals, along with human factors professionals, patient and caregiver advocates, and other industry experts.

Patient Labeling

Medical device patient labeling includes any medical device information that is intended for a lay audience. Examples of patient labeling include: medication guides, patient package inserts and instructions for use. Presentations from patients, caregivers, and home healthcare providers provided some important context on how medical devices may be used in the home and how patient labeling can best support patients and caregivers. Typically, device training occurs when a patient is discharged from a hospital or other healthcare facility. This can be a very difficult and high stress time to be learning how to use a complex device. There are many distractions and patients and caregivers can be overloaded by information. Access to easy-to-understand information is critical and improving traditional written instructions is only part of the solution. More novel approaches to communicating information such as visual “quick start guide” instructions, online information repositories and social media tools provide possibilities. However, some major caveats need to be considered, including low literacy levels and limited access to technology for many patients in the United States.

Labeling Guidance

Presenters from CDRH, CDER, and Industry experts reviewed the current state of guidance and research on Patient Labeling. Among the sources for labeling guidance discussed was an updated version of ANSI/AAMI HE75 Human Factors Engineering – Design of Medical Devices standard is about to be released for public comment. This update includes recommendations on how best to incorporate instructional information and materials, including the use of quick start guides, videos, and “new media.”

Throughout the two-day event, several panel discussions were also held to discuss the “nitty-gritty” details of patient labeling. Topics discussed included:

  • What are the key areas of patient labeling?
  • How should the information be presented?
  • How can section headings and placement of key areas be most useful in patient labeling?
  • How can information about the description of the device be most useful?
  • What information is important to include as additional information, appendices & references?

A key human factors point raised when discussing Instructions for Use (IFU) labeling in particular was to approach the design of instructions with the question “What does the end user need to accomplish with this device?,” rather than “What can I tell the end user about the device?.” Key areas identified included:

  • What are the steps to set up the device safely?
  • What are the “red flags” that something is wrong and what should I do or whom should I call in this situation?

Other suggestions included the use of a Frequently Asked Questions (FAQ) section that would mimic the dialog between a patient and Health Care Provider. Also it was suggested that headings be kept simple and usable, and the use of “generic nouns” be avoided. For example, “Do not use if…” is a much more meaningful section heading than “Precautions.”

The Role of Human Factors

Stakeholders agreed that Human Factors testing, including both whole device testing (which incorporates device labeling in realistic use scenarios) and separate label comprehension testing with representative end users is extremely beneficial in developing effective labeling that supports safe and effective device use. Human Factors tools, such as task analysis, are also considered important inputs to developing labeling.

Human Factors MD provides a broad range of Human Factors services related to device labeling, including labeling development, formative and summative human factors studies and label comprehension testing. Contact us at 800.639.7941 to discuss your specific medical device labeling needs.


ANSI/AAMI HE75:2009. Human Factors Engineering—Design of Medical devices. Arlington, VA: Association for the Advancement of Medical Instrumentation.

U.S. Department of Health and Human Services, Food and Drug Administration, Center for Devices and Radiological Health (2001, April 19). Guidance on Medical Device Patient Labeling; Final Guidance for Industry and FDA Reviewers.

Links for Additional Information

Comments on the workshop (regardless of attendance) and the current guidance document are invited at [Docket No. FDA-2000-D-0067].

Webcasts and presentations from the Medical Device Patient Labeling public workshop.


IEC 62366-1:2015 – More Than A Checkbox


In February, the International Electrotechnical Commission (IEC) published IEC 62366-1:2015, Medical devices – Part 1: Application of usability engineering to medical devices, which revised and replaced both the IEC 62366:2007 and IEC 62366 Ed 1.1:2014. That same month the Association for the Advancement of Medical Instrumentation (AAMI) and the American National Standards Institute (ANSI) approved and published it as ANSI/AAMI/IEC 62366-1:2015. Moreover, earlier this month the Food and Drug Administration (FDA) added both the IEC (RN 5-95) and ANSI/AAMI/IEC (RN 5-96) versions to their list of recognized consensus standards.

The updated standard divides IEC 62366 into two parts: IEC 62366-1 and IEC/TR 62366-2. The former is a normative standard that provides requirements on how to optimize medical device development through a Usability Engineering Process in order to mitigate use-associated risks. The latter, which hasn’t been published yet, is a technical report that offers guidance to medical device manufacturers on compliance with IEC 62366-1, along with in-depth information on appropriate methods to apply during the Usability Engineering Process. It is expected that this technical report will be approved and published in 2016.

IEC 62366-1 Overview

The 50-page document is divided into five sections (Scope; Normative References; Terms and Definitions; Principles; and Usability Engineering Process) and annexes (1 normative and 4 informative). While the basic overall structure is similar to the previous editions, numerous changes have been made to IEC 62366-1. The revisions were prompted for a number of reasons including: updating Usability Engineering concepts; streamlining the Usability Engineering Process; bolstering linkages with ISO 14971:2007; and harmonizing it with the FDA Draft Guidance Applying Human Factors and Usability Engineering to Optimize Medical Device Design. Some specific changes include:

  • “Application Specification” changed to “Use Specification”
  • “Usability Specification” changed to “User Interface Specification”
  • “Frequently Used Functions” and “Usability Verification” removed
  • “Primary Operating Functions” modified to focus on medical device safety
  • “Formative Evaluation” added
  • “Usability Validation” changed to “Summative Evaluation”

Usability Engineering Process

As noted previously, the standard requires that a company use a Usability Engineering Process to ensure development of a safe and usable medical device that minimizes the risks associated from use errors. The nine-step process includes:

  1. Prepare Use Specification
  2. Identify user interface characteristics related to safety and potential use errors
  3. Identify known or foreseeable hazards and hazardous situations
  4. Identify and describe hazard-related use scenarios
  5. Select the hazard-related use scenarios for summative evaluation
  6. Establish User Interface Specification
  7. Establish User Interface Evaluation Plan
  8. Perform user interface design, implementation and formative evaluation
  9. Perform summative evaluation of the usability of the user interface

All of the activities highlighted above are captured in the Usability Engineering File that becomes part of the overall Design History File for the medical device.

Final Thoughts

Compliance with standards is just one part of a robust human factors program for medical device development. But, on its own it is insufficient. It also requires, among other things, having skilled professionals with the appropriate training and experiences to ensure that medical devices are safely designed, developed, and deployed. But, not all medical device companies employee human factors experts. In those instances, an experienced human factors consultancy that focuses on the healthcare domain is needed.

Human Factors MD helps medical device and pharmaceutical clients create innovative products that are safe, usable, and effective. Our team of talented human factors experts supports our global clientele throughout the product development process. Contact us to learn how we can provide a custom solution that fits your specific needs.


ANSI/AAMI/IEC 62366-1:2015. Medical devices – Part 1: Application of usability engineering to medical devices. Arlington, VA: Association for the Advancement of Medical Instrumentation.

IEC 62366 Ed 1.1:2014. Medical devices – Application of usability engineering to medical devices [Consolidated Version]. Geneva, Switzerland: International Electrotechnical Commission.

IEC 62366-1:2015. Medical devices – Part 1: Application of usability engineering to medical devices. Geneva, Switzerland: International Electrotechnical Commission.

ISO 14971:2007. Medical devices – Application of risk management to medical devices. Geneva, Switzerland: International Organization for Standardization.

U.S. Department of Health and Human Services, Food and Drug Administration (2011, June 22). Draft guidance for industry and Food and Drug Administration staff – Applying human factors and usability engineering to optimize medical device design.


FDA Offers New HF Guidance

This past June 2011 marked the release of a new guidance document from the FDA titled Applying Human Factors and Usability Engineering to Optimize Medical Device Design. It is the first new guidance on human factors from the Agency in more than 10 years and it marks a significant evolution in the Agency’s thinking about the role of human factors in improving medical device safety. Like its earlier counterpart , the guidance focuses on how human factors methods can be used to identify and mitigate use-related hazards. But the new guidance is much more prescriptive and raises the bar for device manufacturers. It includes new requirements for human factors validation testing. These requirements apply not just to “traditional” device manufacturers, but to companies producing “combination products” as well – drug products delivered using specialized syringes, injectors, and inhalers.

What is Human Factors Anyway?

Human factors is a marriage of psychology and engineering. It is the application of our knowledge of human capabilities, limitations, and predispositions to the design of work, workspaces, and technology. Of course, technology includes medical devices.

Poorly designed devices put patients and device operators at risk. Problems arise when there is a mismatch between how a device should be used and the physical, perceptual, or cognitive abilities of the person using it. For example, the thumbwheel on a glucose monitor may be too difficult for a diabetic with neuropathy to operate, information on a patient monitor may be too small for a nurse to read accurately from across the patient’s bed, or the sequence of steps to set the dose and prime an injector may be too lengthy for an elderly patient to remember. Environmental factors such as lighting, noise, and vibration can create use-related risks as well. Imagine setting up and adjusting a heart monitor in a speeding ambulance. And situational factors such as lack of sleep or the competing demands of a busy ER can make operating an already complex and non-intuitive device more difficult.

Use-related hazards arise when design problems trigger use errors that pose risks to patients or device operators. The good news is that human factors engineering can play a valuable role in identifying, evaluating, and addressing use-related hazards during device design. A thorough human factors analysis considers all aspects of the user, intended use, the use environment, and the device user interface:

  • User Considerations include who will use a device (a physician, nurse, patient, non-medical care giver): their physical strength, dexterity, and stamina; their attitudes, and emotional states; and what training they will receive and their knowledge of related devices.
  • Intended Use includes what the device will be used for (e.g. self-administration of a medication), or the work the device is designed to support (e.g., monitoring a patient’s oxygen saturation level).
  • Use environments may be hospital ICUs, labs, physician offices, emergency transport vehicles, patient homes, and public spaces; the environment may be crowded or cluttered, dark or well lit, quiet or noisy; environments may include other equipment or require the user to engage in other activities while operating a device.
  • The Device User Interface includes not only switches, dials, touch screens, icons, menus, indicator lights and alarms, but operating instructions, labeling, packaging, and training materials as well.

Well-designed devices accommodate user and environmental factors. Their user interface is consistent with a user’s abilities and operate in ways that are aligned with a user’s experience and expectations. They facilitate correct actions and prevent or discourage use errors that pose risks to patients or users. Human factors engineering provides the knowledge and methodology to reliably create well-designed, user- and patient-friendly devices.

The New Guidance: Applying Human Factors to Optimize Medical Device Design

The new guidance provides an excellent introduction to human factors and its application to medical device design. It is a well-written Human Factors 101. Like its predecessor guidance released in 2000, it describes how human factors methods can be applied during device design to effectively manage use-related risks. But the new guidance also introduces new requirements for Human Factors Validation Testing and outlines how human factors activities should be summarized and reported.

Human Factors Validation Testing

In principle, device manufacturers will need to conduct human factors validation testing for their device if their risk analysis has found a moderate to high risk of use error or the FDA feels testing is warranted to justify its concerns about human factors issues. In practice, the FDA is requesting human factors validation tests in support of submissions for a broad range of devices. This includes combination products utilizing drug delivery systems such as an injector or inhaler. Human factors validation studies have become part of the review for approval of many New Drug Applications (NDAs). These reviews are facilitated by the Office of Combination Products working in conjunction with the Human Factors Team within the Center for Devices and Radiological Health (CDRH) and the Center for Drug Evaluation and Research (CDER).

For most device manufacturers, human factors validation testing requires conducting a simulated use test, in which a minimum of 15 prospective users for each distinct user population are asked to operate the device in a meaningful way, in a realistic, but simulated environment. The test should be structured to mimic actual use, utilize a production version of the device, and be sufficiently sensitive to capture use-related problems, if they exist. This means test participants must be representative of actual users; the testing must be focused on the highest-priority tasks or use scenarios; and environmental and situational factors that can affect performance must be incorporated into the test environment (e.g., dim lighting, multiple alarms, distractions). The test should monitor participant performance for evidence of use errors and engage participants (after all test scenarios have been completed) in assessing any use issues that arose during testing.

Finally, test participants must be Americans . The FDA is responsible to US consumers. Rather than entertain arguments from foreign manufacturers about why Canadians or English-speaking Europeans are adequate surrogates, the Agency now requires that testing be done in the US.

The Human Factors Engineering Report
The new guidance also outlines how manufacturers should summarize and report on their human factors engineering activities. Table 1 outlines the FDA’s requirements for a Human Factors Engineering Report. The outline ensures that manufacturers discuss those topics of primary importance to human factors reviewers and follow a format that will facilitate the review process.

Manufacturers should draft the report as a defense lawyer might draft their closing statement in a legal case: first, review the facts of the case (the analysis you undertook to identify and address use-related hazards), then the evidence assembled (especially the results of your validation test), and finally, why the facts and evidence support the case (your definitive claim that the device can be used safely, and why any residual risks are acceptable without further efforts at mitigation).

Section Recommended Content in Each Section
1 Analysis of Intended Users, Uses, Use Environments, and Training.

Describe your intended users, intended use, and context of use. Include a discussion of critical factors that influence user performance, including differences among distinct user groups, aspects of the use environment, or situational factors present in the context of use. Discuss whether device users will require training and how that training will be provided in practice.

2 Device User Interface.

Provide a graphical depiction of your device user interface and a verbal description of device operation.

3 Summary of Known Use Problems.

Summarize your analysis of known issues with predicate or related devices and what design modifications where introduced for your device to mitigate these issues.

4 User Task Selection, Characterization, and Prioritization.

Summarize your risk analysis methods and the use-related hazards you identified. Relate these risk to user interactions to prioritize user tasks by their level of risk. Critical user tasks must be included in your validation testing protocol.

5 Summary of Formative Evaluations.

Discuss formative usability testing conducted during your device’s design. Discuss key findings and design modifications introduced as a result, or insights that informed the design of your validation testing protocol.

6 Validation Testing.

Describe your methodology, including rationale for selection of test participants, approach to training, critical tasks and scenarios studied, technique for capturing unanticipated use errors, and definition of performance failures. Test results should review task failures and include an analysis that incorporates subjective assessments by participants about those failures.

7 Conclusion.

Provide a statement that your device is safe and effective for intended users, uses, and use environments. Then discuss how the work you performed (described in the previous sections) supports this conclusion. Discuss any residual risk and provide a rationale for why further attempts at mitigation are not warranted.

Table 1. Outline for the Human Factors Engineering Report.

Canada, Europe and Beyond?
The new guidance is, of course, specific to the FDA and devices bound for the US market. What about Health Canada, Europe, or other jurisdictions? While Health Canada regulations do not deal specifically with human factors (a search of the Health Canada website for the term “human factors” turned up little in the way of guidance or requirements) Health Canada is following the FDA’s direction and has begun to ask device manufacturers to conduct human factors validation testing to support their submissions.

Manufacturers are already required to comply with ISO/EN 62366: Medical devices – Application of usability engineering to medical devices, in order to gain CE Marking for sale of their devices in the European Union. ISO/EN 62366 is similar in intent to the FDA’s new guidance document and includes a requirement for validation testing.

Moving Forward
If your company is a medical device manufacturer or is planning a new drug application that includes a drug delivery device such as a syringe, injector, or inhaler, plan on conducting a human factors validation, in the United States, to support your regulatory submission. Don’t wait for a request from a reviewer. Manufacturers need to start human factors work early in their product’s design. Companies will not meet the FDA’s requirements for a well-designed human factors validation study if they have not conducted an analysis of device users, use environments, and situational factors that affect how well people can use the device; prioritized the risk of user interactions; and identified and taken steps to mitigate potential use-related hazards. The very good news is that doing this human factors work will ensure that your company develops a safer, more usable product.


Formative Usability Testing

The simplest, most effective way to understand how to improve your product is to watch people use it.

Human Factors MD conducts Formative Usability Testing for clients to evaluate the usability of their medical software or device design. We put early product concepts or design prototypes into the hands of users and have them complete real activities under our observation. Six to eight users are sufficient to put a design through its paces. We measure how well people do, where they have problems, and how they experience the design. When testing is complete, our clients know which aspects of their design work well and where to focus efforts at improvement.

Solves These Problems

  • We are investing heavily in the development of a new generation of product. But how can we be sure we have a winner?
  • Clinicians won’t use our device unless it’s simple and easy to operate. How do we ensure that our engineers are on the right track?
  • How do we meet our design verification objectives? How can we verify that our design outputs match our design inputs?

Our Approach

Conducting formative usability testing as part of an iterative design strategy is the most reliable way to develop a truly usable product. The very good news is that formative usability testing can be effective with as few as six to eight participants. Moreover, depending upon the design issues under evaluation, usability testing can be conducted using simple, low fidelity paper or foam mockups or higher fidelity software or presentation prototypes.

But for usability testing to be effective, it needs to conducted well. Usability testing isn’t simply about bringing users around a table to view and talk about your design. A usability test is not a focus group. For usability testing to be an effective tool for understanding user interface design strengths and weaknesses it needs to engage actual users in performing real work. Actual users. Performing real work. Using realistic clinical data. In a realistic setting.

We’ll work with clients to plan an effective usability test: to define the test objectives, prototype requirements, and activities test participants will perform to evaluate the design. We develop a participant screener and recruit representative users. We host and conduct the testing, keeping a video-log for subsequent evaluation. We analyze the results, prioritize usability issues, generate design recommendations, and summarize the key findings and recommendations in a presentation to our client’s development team.


  • Provides quick, cost-effective, and actionable feedback from real users.
  • Identifies usability strengths and prioritizes usability weaknesses.
  • Satisfies design verification requirements.


A Usability Test Plan, Participant Screener, Results Presentation, and video-footage.


Usability Bench Test™

Our Usability Bench Test™ provides a quick and cost-effective evaluation of potential usability issues with a software application or medical device user interface. The Bench Test can be performed at the earliest stages of your product’s development, while there is still an opportunity to introduce effective design solutions.

Solves These Problems

  • How do we identify potential usability issues early enough in the design process to address them effectively?
  • How to we identify usability issues that could negatively effect user acceptance and satisfaction?
  • We conduct usability testing when we have a working prototype, but what can we do earlier in the process to ensure we are on the right track?
  • How can we verify that the design we have meets our design input requirements?

Usability Bench Test™ Defined

The Usability Bench Test™ combines elements of several proven human factors techniques, including Task Analysis and Heuristic Review. The test is performed by one or more human factors and design experts, who take the following factors into consideration:

  • The design of the user interface, instructions for use, and packaging.
  • The specific steps (i.e., task steps) required to use the device safely and effectively.
  • The device use environment (the environmental, social, and organizational conditions under which the device is likely to be used).
  • The motor, perceptual, and cognitive capabilities and limitations of the target user population (i.e., what users can do relative to the requirements of the task).
  • The predispositions of the target user population (what users are likely to do given their expectations and experience with the device).
  • General human factors principles for good design (e.g., Provide unambiguous and timely feedback on use actions and device states, Provide a clear conceptual model, Make things visible, Anticipate errors, Reduce memory load).
  • Relevant standards, including the AAMI’s HE75 Human factors engineering: design of medical devices.

Usability problems are identified and prioritized based on their impact to the user and likelihood of occurrence. Recommendations for design or labeling changes aimed at addressing the problems are provided.


Written report suitable for inclusion in a design history file and/or a PowerPoint™ presentation summarizing key findings and recommendations for design or labeling changes.


Human Factors and the QSR

FDA LogoAs a manufacturer, you are required by FDA to demonstrate how human factors considerations were met during your product’s development. To assist manufacturers in understanding the regulations, FDA issued several guidance documents to support its human factors initiative, including Do It By Design: An Introduction to Human Factors in Medical Devices and Medical Device Use-Safety: Incorporating Human Factors Engineering into Risk Management. However, the “teeth” behind their human factors requirements lay in Section 820.30 of the Quality Systems Regulation or QSR, in paragraphs c, f, and g: