What is human factors & usability testing?

Human factors testing is the structured evaluation of how people interact with your device: its interface, labelling, instructions, and the steps required to use it safely. The goal is to find and remove use errors before they reach a patient, and to show regulators that intended users can operate the finished device safely and effectively. It is required under IEC 62366-1, ISO 14971, FDA human factors guidance, and EU MDR.

Where it is done well, use-related risk is designed out early and the evidence holds up under review. The work happens in two types:

Formative usability evaluation

Iterative studies run throughout design with small groups of representative users, to surface usability problems and feed them back into the design while changes are still inexpensive. Perdigó runs these in-house.

Summative usability testing

The confirmatory study on a finalised device, measured against pass and fail criteria drawn from the use-related risk analysis. It is run by a specialist test house. Perdigó prepares the device and the risk evidence it is built on.

Usability engineering at Perdigó

We build the human factors evidence as the design takes shape, so the record is current and traceable when your submission is assembled.

Usability engineering plan and URRA

We author the usability engineering plan at kickoff, defining what will be tested, at what fidelity, with which user groups, and at which stages. In parallel we produce the use-related risk analysis, mapping user tasks, assessing where a use error could cause harm, and identifying the critical tasks. We maintain it as the design changes.

Formative evaluations across stages

We run formative evaluations from early concepts through to near-final devices. Each round probes the specific interaction risks in the URRA, and the findings feed back into the design. Every round is documented.

Human factors engineering documentation

We build the development-stage human factors documentation as we go: context of use, user and use-environment profiles, interface description, formative evaluation history, and critical task analysis. It grows with the programme rather than being assembled at the end.

Human factors & usability is development-long

Usability engineering starts with the first design, not the last.

→ Early design: User research defines the intended users, the context of use, and the tasks they perform. The use-related risk analysis is started and design concepts are assessed against real use scenarios.

→ Concept and detailed design: Formative evaluations run as the design evolves, from low-fidelity concepts to higher-fidelity prototypes. Each round tests handling, labelling, instructions, and use sequences, and updates the risk analysis.

→ Validation: With the design finalised, summative testing confirms that representative users can perform the critical tasks safely. The scope is drawn directly from the risk analysis and formative history.

→ Post-market: Design changes, new markets, or surveillance findings can require further evaluation. The existing risk analysis and documentation set the baseline for scoping it proportionately.

medical device design drawings and prototypes

Human factors validation support

Summative testing is run by a specialist test house, and its success depends on how well the study is scoped and prepared. At Perdigó, we support validation through comprehensive and compliant documentation package in addition to test units.

Usability engineering plan

The document that defines the scope and method of the whole programme.

Use-related risk analysis (URRA)

The living analysis of user tasks, use errors, and critical tasks that defines the test scope. Required under IEC 62366-1 and ISO 14971.

Formative evaluation reports

One per round: objectives, participants, method, findings, and the design responses they drove.

Human factors engineering (HFE) file

The consolidated development-stage record: context of use, user profiles, interface description, and critical task analysis.

Summative test scope package

The risk and critical-task evidence prepared for your test house, and to support FDA pre-submission review where it applies.

Instructions for use (ISU) and labelling

Authored and evaluated through formative testing for comprehension and completeness.

Use-related residual risk analysis

The post-test assessment justifying that any remaining use-related risk is acceptable against clinical benefit.

Test units

Production-representative units from the pilot manufacturing stage, ready for the test house.

Why Perdigó Medical for human factors testing?

Continuity

Your use-related risk analysis and formative records are maintained from the first design decision, so the summative test scope and documentation are ready at validation, not rebuilt under deadline. If you engage Perdigó at a later development stage, we assess the current design and files, perform a gap analysis, and execute and document whatever is needed.

Engineering expertise

When testing surfaces a use error, the engineers who developed your device can redesign it and return it to the risk file, rather than hand the problem back to you.

Independence

We hold no preferred-supplier arrangements. We help you choose the summative test house on fit alone: regulatory track record, experience with your user group, and the right use environment.

Cross-market compliance

We prepare human factors documentation for EU MDR, FDA, and UKCA submissions, working to each market's requirements, including where IEC 62366-1 and FDA guidance differ on scoping critical tasks.

Trusted by medical device leaders

We have helped medical device innovators turn ideas into market-ready products.

"Perdigo is a great partner for your device development. Their expertise and capacity to adapt to your needs makes them a great choice to work with."

Laura Andrade

R&D, Innovation & New Products Associate Director, Insud Pharma

“Perdigó's risk management work, engineering documentation and expert advice have supported the successful regulatory submission and approval of the Airway Shield device."

Julio M. Alonso

CEO and Chief Medical Officer, Airway Medical Innovations

“Perdigó's expertise in healthcare engineering and product development was crucial to the progress of our device. Their technical knowledge, flexibility, and total dedication were invaluable, and were essential in ensuring the successful development of the device.”

Joan Vieyra

CTO The Blue Box Biomedical Solutions

"At Heecap, we're excited to be working with Perdigó to transform our product from a prototype to a market-ready system. It's the professional, multidisciplinary team we work with every day and whose expertise gives us the confidence to deliver a high-quality, successful end product."

Sofia Ferrerira

CTO & co-Founder at Heecap and Innovation Engineer at Hospital Sant Joan de Déu Barcelona

Clear, streamlined engagement

Working with Perdigó is straightforward by design.

01 Scoping call

We discuss your device, where it stands, and your objectives. There is no commitment at this stage, simply an honest view of whether we are the right fit.

02 Needs assessment meeting

Our engineers review your device and any existing usability files in detail, so both teams are aligned before any work begins. An NDA is signed around this point.

03 Proposal

You receive a clear proposal that defines the engagement scope, deliverables, timeline, and investment.

04 Kick-off and collaboration

We run the formative evaluations, maintain the use-related risk analysis and human factors documentation, and prepare the summative test scope. You receive regular progress updates and checkpoints where key decisions are agreed together.

05 Handover and next steps

You receive the human factors evidence package and support through summative testing with your test house, ready to move into regulatory submission.

Perdigó's medical device regulatory team

FAQs

1. What is human factors testing for medical devices?

Human factors testing is the structured evaluation of how users interact with a medical device: its interface, labelling, instructions, and use sequences. It identifies and removes use errors and demonstrates to regulators that intended users can operate the device safely. It runs in two forms, formative testing during development and summative testing on the finished device, and is required under IEC 62366-1, ISO 14971, FDA human factors guidance, and EU MDR.

2. What is the difference between formative and summative usability testing?

Formative testing is iterative and developmental, run during design with small groups of representative users to find and fix usability problems. Summative testing is confirmatory, run on a finalised device against predefined pass and fail criteria to demonstrate it can be used safely. Formative testing informs the design; summative testing validates the result.

3. What is a use-related risk analysis (URRA)?

A URRA maps every task a user performs with a device and assesses where errors could occur, what harm could result, and how severe it would be. It identifies the critical tasks, those where a use error could cause serious harm, which define the scope of both formative and summative testing. Regulators use it to judge whether a human factors programme was appropriately scoped.

4. Who conducts summative usability testing?

Summative testing, also called human factors validation, is typically conducted by a specialist human factors test house or clinical research organisation. The device developer prepares the test scope, the use-related risk analysis, and the critical task documentation, and provides the production-representative units. The test organisation recruits participants and runs the sessions under simulated use conditions.

5. How many participants does summative usability testing need?

There is no fixed number. A pilot batch is typically tens to a few hundred units, sized to the device and what the batch needs to support, such as design validation, clinical evaluation, or a regulatory submission. The quantity is set by how many units are required to demonstrate the process runs consistently and to supply the studies that follow. Volumes stay well below commercial manufacturing, since the purpose is to prove the process before full scale-up.

6. When should human factors testing start?

At the beginning of development. The usability engineering plan and an initial risk analysis should be in place before the first design decisions are made. The earlier formative evaluations begin, the cheaper problems are to resolve, and the better understood the critical tasks are by the time the device reaches summative testing.

Human factors testing for medical devices