EN 62366-1:2015+A1:2020 requires manufacturers to define the use environment and the intended users. Under MDR, the internal market is 27 member states with 24 official languages, multiple scripts, different colour associations, and different conventions for how numbers, dates, and warnings are read. A use specification that silently assumes one culture will fail summative evaluation in another. The fix is to name every target market explicitly in the use specification and to design user interface and information for use accordingly.

By Tibor Zechmeister and Felix Lenhard.

TL;DR

  • EN 62366-1:2015+A1:2020 clause 5.1 requires the manufacturer to prepare a use specification, including intended use environment and user groups. Culture is part of that environment.
  • MDR Annex I §5 obliges manufacturers to reduce risks linked to ergonomic features and to the environment of use, factoring in the training and physical condition of intended users.
  • MDR Annex I Chapter III §23 requires the label and instructions for use to be in an official Union language accepted by each member state where the device is made available.
  • Colour meaning, icon interpretation, reading direction, and number formatting vary across the 27 member states. A green button is not neutral everywhere. A red triangle is not universally a warning.
  • Use specifications that only list "the European Union" as the market are incomplete. Name the member states. Build the usability engineering file so additional markets can be added with a change control, not a rewrite.
  • Summative evaluation under EN 62366-1 must recruit users that match the declared use specification. If the specification names France and Germany, users from France and Germany must be tested.

Why this matters

Tibor has audited usability engineering files where the use specification stated "intended market: European Union" and then recruited eight summative participants from a single city. The file passed internal review because the team conflated the legal market with the user population. The notified body raised a nonconformity. Under EN 62366-1:2015+A1:2020, the use environment is not only a legal territory. It is the physical, linguistic, and cultural setting in which real users will touch real devices.

Felix has seen the same pattern on the startup side. A team ships an elegant product, wins first clinical partners in the Nordics, then cannot reproduce the results when a Spanish hospital group pilots the same device. The device was identical. The users were not. Colour codes on the display, icon placement, and the pacing of the on-screen instructions were all tuned to a design sensibility that did not translate.

Neither the MDR nor EN 62366-1 uses the word "culture" explicitly. But both demand that the intended users and use environment be defined and that the residual use error is acceptable for those users in that environment. Culture sits inside that definition whether the author names it or not. The honest move is to name it.

What MDR actually says

MDR Annex I, the General Safety and Performance Requirements, drives the usability obligations for every device on the European market.

Annex I GSPR §5 requires that manufacturers reduce, as far as possible, the risks linked to the ergonomic features of the device and the environment in which the device is intended to be used. It explicitly lists technical knowledge, experience, education, training, and the use environment as factors the manufacturer must account for.

Annex I GSPR §22 applies to devices intended to be used by lay persons. It requires the design to account for the skills and means available to those lay users and to minimise incorrect handling.

Annex I Chapter III §23 governs the information supplied with the device. It requires the label and instructions for use to be provided in an official Union language or languages accepted by the member state in which the device is made available to the user or patient. That requirement sits on top of any usability work. Translating the IFU is not optional, and the translation itself is part of the accompanying information that EN 62366-1 treats as part of the user interface.

The harmonised standard EN 62366-1:2015+A1:2020 operationalises these GSPRs. Clause 5.1 requires a use specification that names intended medical indications, patient populations, intended users, conditions of use, and the use environment. The standard does not enumerate cultures, but it requires the manufacturer to describe the conditions under which the device will be used with enough precision that representative users can later be recruited for summative evaluation. A use specification that cannot be mapped back to named member states cannot be tested credibly.

When EN 62366-1 work feeds into the risk management process under EN ISO 14971:2019+A11:2021, every hazard-related use scenario that depends on a culturally specific assumption becomes a documented risk. The quality management system under EN ISO 13485:2016+A11:2021 clause 7.3 on design and development must ensure that design inputs capture these assumptions and that design outputs can be verified against them.

A worked example

A startup is developing a Class IIa wearable cardiac event recorder intended for home use. The device has a small OLED display, two physical buttons, and a companion mobile application. The team is based in Vienna. The founder wants to place the product in Austria, Germany, Italy, and France within the first year, and Spain and Poland within the second.

The use specification, clause 5.1 of EN 62366-1:2015+A1:2020, lists exactly those six member states as intended markets. It lists adult lay users with no prior medical training as one user group and general practitioners as a second. Use environments are home, clinic, and during outpatient daily activity.

From that single honest statement, several design decisions follow.

Language layouts. The companion application must render user interface strings in German, Italian, French, Spanish, and Polish. String expansion in German routinely runs thirty per cent longer than the English source. Polish diacritics require font coverage that a minimal Latin font set does not provide. The user interface specification captures maximum string length per UI element.

Colour semantics. The OLED display uses a green arc for "recording normally" and a red outline for "contact lead" warnings. The team runs formative evaluation with Austrian and Italian users early. Results confirm those colours work as intended for both groups. The team documents the decision and the evidence, because an auditor will ask why the default mapping was accepted.

Icon interpretation. A pill icon means medication reminder in the companion app. Formative testing in France and Poland finds that interpretation holds. The team does not assume it and does not test in only one country.

Reading direction and information density. All target languages are left-to-right Latin script, which simplifies the UI. The IFU is prepared for each language with the same layout grid. Chapter III §23 of MDR Annex I drives the linguistic coverage, not internal opinion about which markets "really matter".

Summative evaluation recruitment. EN 62366-1 requires representative users. The summative evaluation plan recruits 15 lay users and 5 general practitioners per member state, splitting across at least three of the six listed markets. That is a judgment call with the notified body. What is not a judgment call is that the notified body will ask why no users were recruited from France if France is listed in the use specification.

The usability engineering file references these decisions in one place. When Spain and Poland are added formally in year two, the design change goes through the change management process under EN ISO 13485:2016+A11:2021 clause 7.3, the use specification is revised under version control, additional summative sessions are planned, and the risk file is updated accordingly.

The Subtract to Ship playbook

A lean startup cannot run summative evaluations in all 27 member states. A lean startup can refuse to pretend it has. The playbook is about honesty in the use specification and ruthless reuse of one usability engineering file.

Step 1. Name the markets. In the use specification, list the exact member states you will place the device on in the next 12 months. No umbrella phrases. The notified body reads this first.

Step 2. Separate design choices from culture assumptions. Every icon, every colour, every sound, every haptic cue that could carry a cultural meaning is listed with the evidence that supports it. EN 62366-1 calls this part of the user interface specification. Treat it as such.

Step 3. Run early formative evaluation in at least two culturally distinct markets. Clause 5.7 of EN 62366-1 allows formative evaluation throughout development. Use it to expose cross-cultural assumptions early, when fixes are cheap.

Step 4. Build the summative plan around the named markets. Do not run summative evaluation only in the home market if the use specification lists more. The notified body will compare the two documents.

Step 5. Treat the IFU as part of the user interface. MDR Annex I Chapter III §23 requires translation. EN 62366-1 treats the IFU as part of the user interface. Combine the two obligations: translate the IFU into every language listed in the use specification, and run IFU usability with native speakers during summative evaluation.

Step 6. Use change control for market expansion. When market number seven or eight opens, the design and development procedure under EN ISO 13485:2016+A11:2021 clause 7.3 handles the change. The use specification is versioned, the risk file is updated, and additional summative data is collected. This is the moment where a well-built file pays back. A badly built file is rewritten.

Step 7. Do not translate into markets you have not tested. A Polish IFU without Polish usability evidence is an auditor trap. Either test or do not list the market.

Reality Check

  1. Does the use specification for your current device name every member state you intend to place it on in the next 12 months?
  2. For each named member state, can you point to formative or summative evidence collected with users from that country?
  3. Has every icon and colour in the user interface been reviewed against the target markets, or were they chosen by the design team in one location?
  4. Does the IFU exist in every official language required by the member states you listed, and has any of those translations been tested with native speakers?
  5. If you added a new member state tomorrow, would your change control process update the use specification, the risk file, and the summative plan, or would it only update the label?
  6. Are user interface strings bounded by a maximum length that accounts for language expansion, or are they tuned to English?
  7. Does the risk management file under EN ISO 14971:2019+A11:2021 explicitly list hazards that depend on culturally specific assumptions, or are those assumptions invisible?

Frequently Asked Questions

Does EN 62366-1 require us to run usability tests in every country we sell into? No. The standard requires representative users for summative evaluation. Representativeness is a judgment the manufacturer makes and the notified body reviews. What is required is that the users tested plausibly represent the population listed in the use specification. Listing 15 markets and testing in one is not plausible.

What counts as "culturally different" for the purposes of a use specification? EN 62366-1 does not define culture. Tibor treats two markets as culturally different when language, reading conventions, colour associations, or use environment differ enough that a task an intended user performs could be affected. Austria and Germany may behave similarly enough to pool. Spain and Finland usually do not.

Can we ship to a member state that is not in our use specification? No. Under MDR, the intended purpose is what the manufacturer declares. If a market is not in the use specification, the usability evidence does not cover it, the IFU languages may not be present, and placing the device there is a design change that has not been controlled.

Is the IFU really part of the user interface? Under EN 62366-1:2015+A1:2020, yes. The accompanying information, including the IFU and any quick-start guide, is part of the user interface. That is why MDR Annex I Chapter III §23 and EN 62366-1 have to be read together.

What if we want to add another member state later? Treat it as a design change under EN ISO 13485:2016+A11:2021 clause 7.3. Update the use specification, update the risk file, add the language to the IFU, and collect the usability evidence you need for the new user population. A change control is cheaper than a nonconformity.

Sources

  1. Regulation (EU) 2017/745 on medical devices. Annex I, General Safety and Performance Requirements, §5, §22, and Chapter III §23.
  2. EN 62366-1:2015+A1:2020, Medical devices – Application of usability engineering to medical devices.
  3. EN ISO 14971:2019+A11:2021, Medical devices – Application of risk management to medical devices.
  4. EN ISO 13485:2016+A11:2021, Medical devices – Quality management systems – Requirements for regulatory purposes, clause 7.3 Design and development.