Medical device manufacturers are legally obliged to eliminate or at least minimize the risks arising from a lack of usability of their devices.

The IEC 62366-1 standard, entitled “Application of usability engineering to medical devices,” helps to proof that the legal requirements are met.


The following articles will help you get started with the topic of usability and its implementation:

  1. Articles introducing the topic
  2. Articles on the regulatory requirements (EU, FDA, IEC 62366-1)
  3. Articles on activities in the usability process
  4. Possibilities for support

1. Articles introducing the topic

Understanding the term “usability” and how it differs from “user experience” is necessary to understand the regulatory requirements better.

The following article helps to distinguish between the terms “use scenario,” “user story,” and “user task.”

The FAQ on usability for medical devices answers further questions.

2. Articles on the regulatory requirements

The laws and standards set requirements for proving the usability and safety of medical devices.

a) EU requirements

Manufacturers who wish to market their devices in the EU must meet the usability requirements of the MDR respectively IVDR as stated in Annex I.5.

b) Requirements of the standards

Manufacturers should fulfill the requirements of IEC 62366-1 for proof of conformity. The IEC TR 62366-2 technical report, which provides the instructions for use for IEC 62366-1, assists in this regard.

The newer versions of these standards work with the User Interface of Unknown Provenance (UOUP) concept. This saves manufacturers of legacy devices, in particular, unnecessary work.

Some particular standards, in addition to IEC 60601-1, contain further requirements for usability, including those for the primary operating functions of medical devices.

IEC 60601-1-8 is also relevant for manufacturers of ME Equipment in the context of usability. IEC 60601-1-6, on the other hand, is no longer applicable.

The usability engineering process is part of the development process. An article describes the interaction between the usability engineering process and the development process in accordance with ISO 13485.

c) FDA requirements

The FDA recognizes IEC 62366-1 as a “consensus standard” but formulates its usability requirements in its guidelines.

One article presents these FDA guidelines and how they interact, while another describes the human factors engineering process.

The article on FDA- and IEC 62366-1-compliant usability files is particularly relevant for manufacturers who want to market their devices in both markets.

d) Other markets, cross-market

These articles are also helpful:

  • AAMI HE 75: The usability reference book
  • Requirements of the MHRA
  • ISO 9241 family of standards

3. Articles on activities in the usability process

a) Requirements engineering

One of the first steps in usability engineering (a part of requirements engineering) is to define and characterize the user groups. A distinction must be made between primary and secondary user groups.

Both types of user groups can be described using personas.

Once the stakeholders are known and described, stakeholder and thereby user requirements are elicited.

Manufacturers should not confuse user requests and user requirements. Another pitfall is working with requirement specifications and technical specifications.

Please also refer to the overview article on the systematic elicitation of requirements.

b) Dealing with usability risks

The focus of the legal requirements concerns the (safety) risks arising from use errors (not to be confused with user errors).

Manufacturers must consider foreseeable misuse and distinguish it from abnormal use.

The PCA (Perception, Cognition, Action) model is also helpful in risk analysis.

c) Design of user interfaces and instructions for use

Both the stakeholder requirements and the risk analysis influence the legally compliant specification of the user interface. Depending on the user profile, manufacturers must also ensure and prove the accessibility of their devices.


The DiGAV requires proof of accessibility. It can be seamlessly integrated into the usability engineering process.

Several methods are used in the process leading up to the design of the user interface:

The linked articles present the methods and provide tips on how to apply them.

d) Labeling and instructions for use

The instructions for use are considered to be part of the “user interface.” The standard explicitly requires that safety information is evaluated. Please, therefore note the following articles:

e) Evaluation of usability (including usability tests)

In the context of usability, the inspection or assessment is called “evaluation.” A distinction is made between

  1. formative evaluation during development
  2. summative evaluation after development

Methods of formative evaluation

The article Formative evaluation: What the FDA and IEC 62366 require offers a good introduction. Details are described in the following articles:

Methods of summative evaluation

The summative evaluation is carried out as part of a usability test. This article on summative evaluation describes the points you need to pay attention to.

The summative evaluation corresponds to a usability validation, which should be carried out in accordance with the requirements of IEC 62366-1 and FDA.

Please note that older versions of the standard differentiate between verification and validation of usability and not between formative and summative evaluation.

Further information

Further tips can be found in the following articles

4. Support from the Johner Institute

The experts at the Johner Institute support you in all phases of your usability engineering process:

Verification and validation: Differences and definitions

What is the difference between verification and validation, and how are these terms defined? Even standards and regulations use the terms incorrectly or misleadingly. This article 1. Verification a) Definition This definition does not explain what type of “requirements” need to be confirmed by verification. Limiting these requirements to product or component requirements is recommended to avoid…


FDA Human Factors Guidances

The FDA describes its requirements for Human Factors Engineering in two documents: This article What the FDA calls “Human Factors Engineering” (HFE), IEC 62366-1 calls “Usability Engineering“. The FDA defines the term as follows: 1. How the FDA’s “Human Factors Guidances” interact In the introduction to the document “Content of Human Factors Information in Medical…


Formative evaluation: What the FDA and IEC 62366 require

The regulations relevant to usability engineering require formative evaluations. 1. Formative evaluation: Definition and differentiation a) Definitions In its guidance document, the FDA has published its own definition of the term: Thus, it replaces the old definition in the guideline Applying Human Factors and Usability Engineering to Medical Devices: „Process of assessing, at one or…