The first stage of qualification is to determine whether a product is in fact a medical device and not a medicinal substance, a dietary supplement or a cosmetic. This is because different requirements apply to each of these groups.
The next stage is the classification of the medical device. This depends on the intended use of the device and the risk posed by its use. The rules for the classification of medical devices and in vitro diagnostic devices are set out in Annex VIII of the MDR and IVDR regulations.
Criteria for classification of medical devices
There are four main criteria to be considered when classifying medical devices:
- predicted performance and reusability,
- degree of invasiveness, i.e. the type of contact of the device with the human body,
- duration of use of the device,
- rules set out in Annex VIII of the MDR and IVDR regulations,
Degree of invasiveness of medical devices
Based on how intrusive medical devices are to the body and its functioning, they are divided into:
- invasive devices, which penetrate all or part of the body through natural orifices or through the surface of the body,
- non-invasive devices, which penetrate all or part of the body.
- non-invasive products,
- invasive products.
- active devices, i.e. devices whose action depends on an energy source other than the energy of the human body or the force of gravity. They may have a therapeutic effect or be used for diagnostics or monitoring.
Time of use of medical devices
Depending on how long a medical device is expected to be in total use before it fulfils its function, is disposed of or, according to the manufacturer’s recommendation, is replaced by another device of the same type, we divide them into medical devices intended for:
- transient use – whose duration of continuous use does not exceed 60 minutes,
- short-term use – which have a duration of continuous use of between 60 minutes and 30 days,
- long-term use – where the duration of continuous use of the medical device is longer than 30 days,
Regulations for classification
The MDR and IVDR Regulations set out detailed rules for the allocation of medical devices to specific classes. Annex VIII of the MDR Regulation sets out 22 specific rules for medical devices and Annex VIII of the IVDR Regulation sets out 7 classification rules for in vitro diagnostic medical devices.
In ambiguous situations, the procedure is as follows:
- if a device acts in different parts of the body, the basis for classification is the most critical intended use,
- if several rules apply to a given device, the highest class is used,
- if a given device is used together with another device, they shall be classified separately,
- control software shall be classified in the same class as the device, unless it is independent from the device,
- calibrators and control materials shall be classified in the same class as the device with which they are used,
- if the device itself provides the diagnosis or the data decisive for the diagnosis, it shall be considered to be a device enabling direct diagnosis,
Classes of medical devices
For the purpose of classifying medical devices, four classes have been identified, ranked according to the increase in risk: class I, IIa, IIb, III.
Class I medical devices
They carry a low to moderate risk and their use requires general control. This class includes all non-invasive devices unless they are classified in higher classes under the classification rules. Products in this class do not require the involvement of a notified body for conformity assessment before obtaining an EU declaration of conformity – a statement by the manufacturer is sufficient. Exceptions are devices marketed in a sterile state, devices with a measuring function and reusable surgical instruments, which require the involvement of a notified body in this particular respect.
Class II medical devices
They require special control. Class II includes, for example, devices for the storage of blood and other body fluids, dental implants or devices for use on broken skin. Also included in this category are contraceptive devices, devices for recording X-ray images and devices for rinsing disinfection and sterilisation. In Class II, there are two groups IIa and IIb – depending on the risk or mode of action of the device.
Class III medical devices
Their use poses a high risk and must be approved before they can be placed on the market. These include, for example, cardiac monitoring devices as well as implantable devices that come into direct contact with the cardiovascular system or nervous system, breast implants or joint prostheses.
The problem with device classification is that almost every rule contains exceptions. It is therefore necessary to carefully examine all classification rules in order to correctly classify a medical device.
For example, according to Rule 6, invasive surgical devices intended for temporary use generally belong to Class IIa. However, if they are used to control, diagnose, monitor or correct heart defects through direct contact with the heart, they belong to Class III. If, on the other hand, they are devices for the administration of medicinal products, which is done in a potentially hazardous manner, they belong to Class IIb. Reusable surgical instruments, on the other hand, belong to Class I, but still require the involvement of a notified body in the procedure for assessing their conformity.
Classes of in vitro diagnostic medical devices
Classes A, B, C, D have been established for in vitro diagnostic medical devices, self-testing devices and sterile devices are classified separately. What is more with the entry into force of the IVDR regulation, all devices, apart from Class A, require the involvement of a notified body when assessing conformity.
- general laboratory products, equipment, buffers, culture media, dyes, etc.
- instruments specifically designed for use in in vitro diagnostic procedures,
- sample containers,
- the following products for self-testing: pregnancy tests, ovulation tests, tests for determining cholesterol, detecting glucose, erythrocytes, leukocytes and bacteria in urine,
- control materials without assigned quantitative or qualitative values,
- products not included in other classes,
- devices for determining blood groups or tissue compatibility for the purpose of immunocompatibility (with the exception of those belonging to Class D),
- devices intended to detect the presence of infectious agents,
- devices for prenatal diagnosis, including for determining the immunological status of pregnant women and for detecting congenital malformations of the foetus and congenital diseases in the newborn that are life-threatening or result in severe disabilities,
- devices for diagnosis in targeted therapy,
- devices for determining the stage of disease or infectious disease status where this has implications for patient care decisions,
- devices for screening, diagnosis and staging of cancer,
- genetic tests,
- devices for monitoring the concentration of drugs, substances or biological components,
- devices for the care of patients in a life-threatening condition,
- devices for self-monitoring, with the exception of those listed in class B
- devices for performing in tissues the presence of, or exposure to, a transmissible agent to assess suitability for transfusion, transplantation or cell administration,
- detection of a transmissible agent causing a life-threatening disease with a high risk of spreading,
- measurement of the concentration of an infectious agent if its monitoring is relevant to patient care,
- measuring ABO blood group markers, Rh system, Kell, Kidd and Duffy system.
Transitional periods for medical devices
In vitro diagnostic medical devices placed on the market prior to the entry into force of the IVDR Regulation may be made available on the market and put into use until 26 May 2025. Certificates issued under Directive 98/79/EC also expire on that date. Additionally transitional periods have also been set for devices that did not previously require certification.