Medical device testing is a central component of regulatory submission and market access for a medical device and plays a critical role in its commercial success. Teams that delay testing activities risk costly retests and delayed submission deadlines. This guide explains the relevant testing modalities, the regulatory requirements behind them, and how to develop a testing strategy that supports rather than delays your development program.
What medical device testing entails
An overview of the six testing dimensions
Medical device testing is not a single testing procedure, but a structured framework consisting of six testing dimensions:
- mechanical and physical testing,
- biological evaluation,
- preclinical in vivo studies,
- electrical safety,
- software and usability testing, and
- sterilization validation.
The combination a product requires depends on its intended use, type of contact, risk class, and target market. In practice, these four factors form the key parameters of a testing strategy.
What defines the testing strategy: four questions you must clarify first
Before a single test is planned, four questions must be answered:
- What is the product’s intended purpose?
- What is the nature and duration of body contact?
According to ISO 10993-1, the duration of exposure is assessed based on the actual number of contact days, with each day of contact with the body counted as a full exposure day. This may increase the biological risk categorization of many products.
- In which risk class is the product classified?
- What is the target market for the product?
The four test modules and how they build on one another
Module 1: Mechanical and physical tests
Mechanical tests assess physical durability over the entire product lifespan. Moving parts require fatigue testing to assess cyclic material stress and durability. This must be methodologically distinguished from the validation of the shelf life and sterility of the entire system through accelerated aging according to ASTM F1980. This approach is based on Arrhenius modeling principles; since the 2021 revision, appropriate humidity controls must be considered for moisture-sensitive materials.
Module 2: Biological Testing and Biocompatibility (ISO 10993 – Overview)
For products intended to come into contact with the body, a biological evaluation in accordance with ISO 10993 is required, the scope of which is determined on a risk-based basis. The Biological Evaluation Plan (BEP) specifies which test methods are scientifically and regulatorily justified for medical devices. Commonly considered endpoints include cytotoxicity, sensitization, and irritation, depending on the nature and duration of contact. Irritation assessment increasingly relies on in vitro methods such as validated Reconstructed Human Epidermis (RhE) models where applicable. Long-term implants additionally require an evaluation of implantation, genotoxicity, and systemic effects.
Module 3: Preclinical in vivo tests
Mechanical laboratory tests cannot replicate biological effects such as tissue response, endothelialization, or degradation behavior. In these cases, preclinical studies in animal models are typically expected: for long-term implants, cardiovascular products, novel materials, and combination products. In the FDA context, pivotal preclinical studies are generally subject to GLP requirements in accordance with 21 CFR Part 58. GLP-like approaches may be sufficient in certain early feasibility contexts, although the transition to GLP should be planned deliberately and is typically most meaningful once the design is sufficiently stable.
Module 4: Documentation Logic
Every test must be traceable to a specific requirement. This principle is referred to as traceability. The testing requirements for medical devices under the EU MDR Annex I are linked in a traceability matrix with standards, test reports, and risk management outputs. An incomplete matrix can lead to additional questions from Notified Bodies.
Graphic: “An Overview of the Four Test Modules”
Test strategy decisions: What needs to be tested, when, and why order matters
Sequencing strategy: what comes first — bench and in vitro testing — and what may come next: in vivo testing?
The correct sequence for preclinical testing saves costs and prevents duplication of effort. As a practical recommendation:
- mechanical verification and chemical characterization first;
- biocompatibility testing on the finished, sterilized end product;
- GLP in vivo studies only after design freeze on production-equivalent units;
- EMC testing is often performed before electrical safety testing to identify interactions early on (see IEC 60601-1);
How to manage timelines and budget risk: Clarify early on what mature enough for regulatory and development decisions
A comprehensive biological evaluation for a Class III implant (including chemical characterization and toxicological risk assessment (TRA)) can take many months and, for complex Class III implants, may approach a year depending on test scope, laboratory capacity, and iteration needs. Preclinical in vivo studies are added to this. Those who do not plan for this early on will delay the submission date by months.
Mini-Checklist: Key Inputs for a Test Strategy Meeting
You should have the following information ready before a consultation:
- Intended use and intended user group (patients and users)
- Type and duration of skin contact (site of contact, direct/indirect contact, and single vs. repeated or cumulative exposure)
- Regulatory classification: anticipated risk class and target market (EU [MDR], US [FDA], or both)
- Current design status (concept, prototype, post-design freeze?)
What tests does your medical device require?
A structured scoping discussion can clarify which testing strategy aligns with the development stage and target market, and where preclinical in vivo studies are appropriate or necessary.
Frequently Asked Questions About Medical Device Testing
What is the difference between verification and validation in the context of testing?
Verification checks whether the product meets its specifications (“Did we build the device according to specification?”), typically through laboratory testing. Validation checks whether the product meets the needs of patients and users under real-world conditions (“Did we address the intended clinical and user needs?”), through preclinical studies, usability tests, or clinical trials. Both are core elements of design control expectations under the EU MDR and FDA frameworks and build upon one another.
Do I have to perform all tests at the same time, or is there a mandatory order?
There is no legally required order, but there is a logical sequence: laboratory testing and chemical characterization first, biocompatibility testing on the finished sterilized product, GLP in-vivo studies after design freeze, and EMC testing before electrical safety testing. Many tests run in parallel and shorten the overall timeline. An overall V&V plan and the Biological Evaluation Plan (BEP) help establish this sequence.
Can in vitro testing replace in vivo studies?
Partially. The revision of ISO 10993-1 reinforces the prioritization of in vitro methods and chemical characterization according to ISO 10993-18 in accordance with the 3R principle. Irritation tests must now be evaluated primarily using RhE models (ISO 10993-23); data from animal models alone are increasingly classified by Notified Bodies as no longer state-of-the-art. For biological effects such as tissue response, endothelialization, or the long-term effects of degradable materials, in vivo studies necessary in many cases.
How long does a complete testing program take?
That depends heavily on the product type. Simple short-term products without implantation: 3–6 months. Long-term implants with a full battery of biocompatibility tests and a GLP in vivo study: 18–30 months, sometimes longer. Rule of thumb: Always plan earlier than you think, as laboratory capacities and GLP appointment slots are often booked up months in advance.
Sources & further links
External references
- ISO 10993-1:2025 – Biological evaluation of medical devices — Part 1
- FDA 21 CFR Part 58
- ISO 10993-18:2020 – Biological evaluation of medical devices — Part 18
- ISO 10993-23:2021 Biological evaluation of medical devices Part 23
Internal Links
- Bio Testing: A deeper look at biological testing under ISO 10993
- Preclinical Data: How test results feed into the preclinical data package
- Medical Device Classification: Which test types are required for each device class
- Class III Medical Devices: Specific testing requirements for high-risk products
- Simulation Techniques: In-silico testing as a complement to physical test methods
- Manufacturing for Medical Devices: Manufacturing-related testing requirements
Dr. Heiko Ziervogel Lorem ipsum …
Field of expertise: Lorem ipsum
Contact: email address | www.medizin-im-gruenen.de
As of: March 2026 | Last reviewed: March 2026