Instructions for use for medical devices and IVDs in the EU

Poor instructions for use are a common cause of use errors that can result in harm to patients and users. Furthermore, instructions for use for medical devices and IVDs are subject to strict regulatory requirements. The MDR, the IVDR, the FDA and numerous standards establish specific requirements for the instructions for use.

This article will explain how to write instructions for use that:

• help prevent harm to patients, users, or third parties,
• fulfill all relevant regulations and, therefore, pass the audit,
• are user-friendly and, therefore, increase customers satisfaction and your market success.

1. Definition and synonyms

As you can see, instructions for use are generally printed documents accompanying the device intended to inform the user of the intended purpose, safety information, and correct use.

The following terms are often used synonymously:

• Directions for use
• Manual or user manual
• Operating manual
• User guide

All stand for the same.

2. Regulatory requirements for instructions for use

Numerous laws, ordinances, directives, standards, and other regulations establish requirements for instructions for use. These include:

Regulation	Description
Medical Device Regulation (MDR)	Most of the requirements for the instructions for use can be found in Annex I, Section 23.
In Vitro Diagnostic Medical Device Regulation (IVDR)	Most of the requirements for the instructions for use can be found in Annex I, Section 20.
Regulation 2021/2226 on electronic instructions for use	Regulation 2021/2226 governs the conditions under which instructions for use may be made available electronically (eIFU) and the associated requirements. The regulation is currently being revised to allow eIFUs also for lay users of software devices (see here).
IEC 62366-1	The instructions for use are part of the user interface. Therefore, they must be developed following a usability engineering process according to IEC 62366-1.
IEC 60601-1	Section 7.9 specifies what has to be included in instructions for use for medical electrical equipment.
ISO 20417	ISO 20417 replaces EN 1041 and, in Section 6.6 in particular, establishes requirements for instructions for use.
ISO 18113-(1-5): In vitro diagnostic medical devices — Information supplied by the manufacturer – Part 1: Terms, definitions and general requirements – Part 2: In vitro diagnostic reagents for professional use – Part 3: In vitro diagnostic instruments for professional use – Part 4: In vitro diagnostic reagents for self-testing – Part 5: In vitro diagnostic instruments for self-testing	Parts 1-5 of ISO 18113 specify the requirements that IVD instructions for use must meet.
IMDRF/GRRP WG/N52 FINAL:2019: Principles of Labelling for Medical Devices and IVD Medical Devices	The aim of this IMDRF/GRRP document is to establish internationally harmonized requirements for labeling (including instructions for use).
FDA: 21 CFR part 801 and 809	The FDA has a series of requirements for the instructions for use; in 21 CFR part 801 for medical devices and in part 809 for IVDs.
FDA Guidance on Medical Device Patient Labeling	Medical device manufacturers should follow this guidance for device clearing in the USA. It also provides helpful tips for writing instructions for use outside the USA as well.
FDA Guidance: Applying Human Factors and Usability Engineering to Medical Devices	Analogous to 62366-1, manufacturers should follow this guidance when writing instructions for use for the US market.

a) Best practice guides for creating instructions for use

Other standards and guides provide advice on how to write good instructions for use:

• IEC/IEEE 82079-1: IEC/IEEE 82079-1 (the successor to DIN EN 62079) is as comprehensive as it is practical. Even though this standard is not focused on one particular sector, it applies to medical devices as it is the state of the art for preparing instructions for use.
• AAMI TIR 49: In contrast to 82079-1, AAMI TIR 49 focuses on medical devices and provides guidance for the “Design of training and instructional materials for medical devices used in non-clinical environments.”
• ANSI Z535: ANSI Z535 specifies how safety information should be designed, for example how symbols and colors should be used.
• The WHO Guidance: Designing instructions for use for in vitro diagnostic medical devices also provides valuable tips on how to prepare instructions for use for devices that are not IVDs. It even provides a structure and contains text templates.

See chapters 4 and 5 for more information on the content of these guidances.

b) When instructions for use are required and when they are not

MDR requirements

The Medical Device Regulation (MDR) permits to provide no instructions for use  under certain circumstances (see Fig. 1). In Annex I, Section 23.1(d), it states:

“Instructions for use shall be provided together with devices. By way of exception, instructions for use shall not be required for class I and class IIa devices if such devices can be used safely without any such instructions and unless otherwise provided for elsewhere in this Section.”

Evidence that the device can be used safely even without the instructions for use can be provided in two ways:

1. The manufacturer’s risk analysis according to ISO 14971 shows that misuse of the device does not result in a hazardous situation for users or patients. This implies that the device can be used safely even without instructions for use. However, in this case, there is a risk that potential use errors werenot taken into account in the risk analysis. Manufacturers don’t always take every possible use error into account and, in such cases, only observe these use errors in usability tests.
2. This means usability tests are a better way of providing this evidence. If the intended users in the intended use environment do not make any use errors in usability tests, this is objective evidence that the device can be used safely without instructions for use.

According to the IVDR

Similarly, instructions for use are also not required under certain conditions for IVDs (see Fig. 2). However, unlike the MDR, the IVDR does not make this exemption dependent of the class of the device. In Annex I, Section 20.1(d), the IVDR states:

“Instructions for use shall be provided together with devices. However, in duly justified and exceptional cases instructions for use shall not be required or may be abbreviated if the device can be used safely and as intended by the manufacturer without any such instructions for use.

c) How should the instructions for use be provided and in what quantity?

As a general rule, the instructions for use must be provided in paper form. Exceptions are possible under certain conditions (see chapter 5d).

MDR and IVDR both require the instructions for use to be provided with the device.

If the manufacturer supplies several products to a single user and/or location, a single copy of the instructions for use is sufficient if the following conditions are met:

• The provision of only one copy of the instructions for use has been agreed in advance with the buyer and
• copies can be delivered at any time on request and free of charge.

Providing only one copy of the instructions for use is permitted under the same conditions under the IVDR. The prerequisite is that the devices are not for self-testing or point-of-care testing.

Instructions for use do not have to be one (bound) document. In some cases, it may even be better to split the instructions for use into several documents, e.g., into one version specifically for non-professionals and one for professional users or service technicians.

d) Provision as electronic instructions for use (eIFU)

Under the MDR, the manufacturer has the option of providing the instructions for use in electronic form only. Regulation 2021/2226 on electronic instructions for use specifies when instructions for use can be provided in electronic form instead of in paper form.

EU Regulation 2021/2226 on electronic instructions for use does not apply to IVDs. Instead, Annex I, Chapter III, Section 20.1(f) of the IVDR regulates when manufacturers do not have to provide the instructions for use in paper format:

“When the device is intended for professional use only, instructions for use may be provided to the user in non-paper format (e.g. electronic), except when the device is intended for near-patient testing.”

e) Contents of instructions for use 

If we summarize the requirements of the regulations mentioned above, we find that the main contents required are:

f)  Language requirements of instructions for use

Article 10(11) of the MDR and Article 10(10) of the IVDR require the instructions for use to be provided in one or more of the official language(s) of the target country.

For example, in Belgium, the instructions for use must be provided in German AND Flemish AND French.

The notified bodies have provided a helpful list of which languages are required/permitted in which countries. You can download this list here (as a word file!). Unfortunately, the website is very unreliable, so you can also find a list of languages permitted for instructions for use here. The list from the notified bodies is from 2008 and therefore might not be up to date in some respects. It refers to the MDD (93/42/EEC). So, there may be different language requirements for IVDs.

In Germany, the Medizinproduktedurchführungsgesetz regulates the language issue:

8(2) “Devices may only be supplied to users and patients within the scope of this law if the information intended for users and patients is provided in German. In justified cases, the information may also be provided in English or another language easily understood by the user of the medical device, provided this information is intended exclusively for professional users and the safety information is also provided in German or in the user’s language.”

In Switzerland, the instructions for use must always be provided in German AND French AND Italian, regardless of the language area. They can be provided to professionals in fewer than the three official languages or in English provided that the professional agrees and no risks result from this (see MepV Art. 16).

g) Requirements for the translation of instructions for use

Neither the MDR nor the IVDR establish any explicit requirements for the translation of the instructions for use. However, the instructions for use must be comprehensible for the intended users in all target languages. Annex I, Section 23.1(a) of the MDR states:

“In particular, instructions for use shall be written in terms readily understood by the intended user […].”

This places special demands on the translation of the instructions for use from the original language to the target language.

IEC/IEEE 82079-1 and the quality standard for translation service providers ISO 17100:2015 establish requirements for the translation process and linguists. For example, the linguist should have the following skills:

• They should have theoretical knowledge and practical experience of translating medical texts.
• They should be fluent in the original language.
• They should be a native speaker of the target language.
• They should have a certain minimum experience in the field of the text to be translated and must be familiar with the product-specific terminology.

The requirement that the linguist is a native speaker of the target language is likely to be difficult for manufacturers to meet by themselves given there are 24 official languages in the EU. So, we recommend using translation service providers.

3. Process of preparing the instructions for use

IEC 62366-1 and the FDA’s “Human Factors Engineering” guidance require a process for developing a User Interface (UI). The instructions for use are an integral part of the user interface. Therefore, manufacturers must also apply the usability engineering process to the instructions for use. This means conducting usability testing of the instructions for use with representative users.

In addition, both IEC 82079-1 and AAMI TIR 49 provide specific recommendations for establishing a process for creating the instructions for use.

The process for creating the instructions for use should include the following steps:

The process should be applied iteratively. In other words, an evaluation should be carried out at important milestones and the results of the evaluation should serve as input for further development.

4. Typical mistakes and their consequences

a) Mistakes that the Johner Institute’s consultants and auditors regularly encounter

• The information in the instructions for use are incorrect.
• The information doesn’t marry up with the device (anymore) – this is particularly common after software updates.
• Which device or which variants the instructions for use refer to and the version number of the instructions for use are not clear.
• Terms are not defined, consistent terminology is lacking, which encourages misunderstanding.
• The text is incomprehensible, sentences are too long, too many phrases are in the passive voice and too abstract. The text uses technical terms and is not based on the vocabulary of the target group.
• There is no structure or the structure is not clear, making navigation and orientation  difficult.
• Images or other forms of visualization are missing.
• Font sizes are too small and there is no color coding or it is used inconsistently. The same applies to text sizes and text markups, as well as the page formatting and the use of elements such as symbols.
• There is no translation or the translation is poor. Google Translate is a no-go.
• There is only one single, hard-to-understand version of the instructions for use for different device variants and combinations with other devices.
• Content required for understanding and safe use is missing. In particular, the instructions for use do not cover all tasks or the complete life cycle from installation to decommissioning and disposal.
• Superfluous information, e.g., about the manufacturer, bloats the instructions for use.
• The instructions for use were not created by qualified staff but, for example, by untrained developers.
• The manufacturers do not check the effectiveness of the instructions for use, e.g., in a usability test.
• The target group is not taken into account sufficiently.
• Manufacturers do not have process for informing users on errors in the instructions for use after delivery.

b) The consequences of inadequate instructions for use

Again and again, in dozens of usability tests, our consultants have seen use errors resulting from inadequate instructions for use. Problems in usability tests caused by inadequate instructions for use can delay device authorization.

If your device has already been placed on the market with inadequate instructions for use, in the worst case they could lead to harm to patients, users, or third parties.

5. Five tips for writing instructions for use

Tip 1: Get professionals to do the job

Don’t leave the writing of instructions for use to developers or product managers who are not trained for this. You need specialized authors, editors, translators, proofreaders, illustrators, and reviewers.

Tip 2: Specify your readers and your goals

Instructions for use are not intrinsically good or bad. They must be written for the users specified in the intended purpose. Instructions for use for medical professionals will not be the same as those written for lay people or those written for service technicians.

You should write down the goals you want to achieve with the instructions for use. What use errors and therefore which risks do you want to minimize? Which tasks does safe use have to be ensured for?

Tip 3: Use a consistent structure and editorial guidelines

Consistent presentation makes reading easier. Editorial guidelines should make sure that the instructions for use contain the following:

• Subject/heading
• Description
• Aim of the action
• Prerequisite
• Status
• Action
• Result to be achieved
• Warning
• Example
• Images and tables with corresponding legends

When designing instructions for use, you should at least:

• Number each individual page with Arabic numerals
• Write instructions in the imperative, in the active voice and in simple language
• Use verbs and not nouns
• Only describe one action in each step (or a maximum of three logically and closely related actions) Only give one instruction in each sentence
• If you add illustrations, they should be clearly linked to the explanatory text

Manufacturers often write instructions that don’t explain actions clearly enough.

Tip 4: Understand instructions for use as a (continuous) process

Writing instructions for use is a team sport with a lot of steps that have to be defined and planned.

Just like the device, instructions for use must be continuously improved.

Tip 5: Follow ISO 14971, IEC 62366-1 and the FDA guidance document “Human Factors Engineering”

The instructions for use are part of the device. Therefore, they are subject to the regulatory requirements governing usability. IEC 62366:2006 even has a separate section on accompanying documentation.

IEC 62366-1:2015 requires these materials to be treated in the same way as the device itself. This means their usability and the effectiveness of the actions they describe – in this case in the form of guidance in the instructions for use – also have to be evaluated.

Professional companies combine several methods:

• Usability tests / participant observations
• Questionnaires
• Self-assessments
• Expert opinions, inspections, review by experts
• Analysis of feedback on previous versions of the instructions for use

The Johner Institute often reviews instructions for use as part of formative and summative usability evaluations.

6. Conclusion

Writing instructions for use requires the same level of professionalism as developing the device itself. The job should not be seen as a necessary evil and quickly palmed off to people who are not sufficiently qualified for it.

The MDR, IVDR, and certain standards set requirements for the information the instructions for use must contain; specific guidance on how to write usable instructions for use can be found in other standards such as IEC 82097-1 or AAMI TIR 49.

It is essential that manufacturers remember that instructions for use have to be tested in the same way as other risk-minimizing actions, particularly those relating to usability. This means instructions for use should also be evaluated as part of the formative and summative usability evaluations as per IEC 62366-1.

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Change history

• 2022-02-18: Complete revision