Global Regulatory Pulse

Human Factors / Usability Engineering in Product Design and Development

In Consulting, European Market, Regulatory by Stephan Buttron

Use error is a commonly reported failure mode for medical devices. Each year thousands of medical device incidents are reported with severe harm to patients due to use errors in clinical procedures. Are these failures avoidable?

The US Food and Drug Administration (FDA) and European Medical Device Regulations require manufactures to apply principles of Human Factors/Usability Engineering  (HF/UE) principles during design and development of medical devices to identify and mitigate potential harm to patient and user.

Because of the rising instances of UI-induced adverse events, the US FDA has begun to include HF/UE reviews as a routine part of their premarket approval process at the Center for Devices and Radiological Health’s (CDRH) Office of Device Evaluation. This process is described in released guidance issued in February 2016 titled  Applying Human Factors and Usability Engineering to Medical Devices.

In February 2016, FDA released another draft guidance listing highest priority devices necessitating human factors design and review. The list includes, but is not limited to: ablation generators, auto injectors, automated external defibrillators, duodenoscopes, gastroenterology-urology endoscopic ultrasound systems, hemodialysis and peritoneal dialysis systems, infusion pumps, insulin delivery systems, robotic catheter manipulation systems and surgery devices, ventilators, and ventricular assist devices.1 In addition, FDA recommends conducting a risk analysis on any medical device not included in the list of highest priority to determine if there is cause for potential harm to the end users.

Likewise, the international regulatory community has incorporated IEC 62366, Medical devices – Application of usability engineering to medical devices, as a part of the approval process in the European Union and outside. Both the FDA HF/UE guidance and European IEC 62366 outline a process including activities throughout device development culminating in validation testing with the final user interface (UI) design in simulated use environments with target user groups and intended use scenarios.

The current European Medical Device Directive2, the expected new European Medical Device Regulation and the latest revision of Quality Management System standard ISO 13485:2016 3rd Edition3 require HF/UE explicitly for all medical devices as essential requirements for device safety and clinical performance.

However, despite this clear regulatory mandate, it is all too common for device manufacturers to post-pone Human Factors Design and Usability Engineering into the clinical evaluation phase or even worse into the market entry phase.  The latter may explain the rise in post-market safety notices and device recalls.

Common root-causes are often inexperience and ignorance of HF/UE.  Design and development projects prioritize functional, safety and performance aspects without proper understanding of the intended users, the intended uses, the primary use environments, the use scenarios, primary operating functions and the UI from a user’s perspective.

Without this understanding, it is difficult implementing HF/UE principles and processes into the design and development project.  As a consequence, implant delivery systems with complex mechanical functionality and demanding hand-to-eye coordination [e.g. percutaneous Trans-Aortic Valve Replacement procedures (TAVR)] may not be evaluated for adequate human factors design and usability.

As device manufacturers continue to integrate more functions into each piece of medical equipment, HF/UE is a vital part of the product development process.

Worldwide, regulatory organizations have begun a systematic oversight and review process regarding manufacturer compliance with the usability engineering standard IEC 62366 and FDA Human Factors/Usability Engineering guidance documents.

HF/UE activities must be conducted throughout all phases of device design and development including preliminary task and risk analysis, UI design and evaluation and final summative validation testing in simulated use.

The HF/UE process must be included into the overall device risk management process. Final decisions regarding use risk acceptability should be based on the results of simulated use testing with representative users evaluating the presence of any remaining patterns of failures and difficulties on tasks with critical risk implications.

Humans do err. That makes them human. But human errors should not cause harm.


  1. The full listing is available at
  2. European MDD 93/42:M5 – Annex I Section 1
  3. ISO 13485:2016 3rd Edition Medical Devices – Quality Management Systems – For Regulatory Purposes 7.3.3 Design Input

Stephan Buttron currently serves as NAMSA’s Senior Product Development Strategist. Mr. Buttron has over 20 years’ experience in achieving EU, U.S. FDA and other international regulatory medical device approvals and registrations. He has provided global consulting services on regulatory strategy development to medical device manufacturers regarding least burdensome pathways for 510(k)/PMA and MMD-CE mark applications. He has successfully managed FDA pre-submission meetings for Investigational Device Exemption (IDE) pathways with multiple FDA specialty branches. Stephan is considered a key industry thought leader on risk management, and has provided multiple training sessions to medical device manufacturers on structured risk management process per EN ISO 14971 & EU MDD 93/42 as amended with directive 2007/ 47. Mr. Buttron has also provided countless educational opportunities to international organizations regarding medical device design and development issues related to ISO 13485 & EU MDD 2007/47 compliance.