1. Classification of Medical Devices and IVDs


Classification of Medical Devices and IVDs

Once a healthcare product qualifies as a Medical Device, it is assigned to one of the classes laid out in the regulations. The classification of Medical Devices under the MDR and IVDR is based on the intended purpose of the devices and their inherent risks in a manner that is aligned with many other regions of the world. Thus, the classification of Medical Devices is a risk-based system taking into account the vulnerability of the human body and the potential risks associated with the devices. This approach uses a set of criteria that can be combined in various ways in order to determine classification, e.g. duration of contact with the body, degree of invasiveness, local vs. systemic effect, potential toxicity, etc. The criteria can then be applied to a vast range of different Medical Devices and technologies. These are referred to as the ‘classification rules’ and are set out in Annex VIII of Regulation (MDR). The classes range from low to high risk and are often called “risk classes”.

The MDR identifies four classes of Medical Devices (Figure 1, left panel):

  • Class I Medical Devices are low-risk devices.
  • Class IIa Medical Devices are low to medium risk devices.
  • Class IIb Medical Devices are medium to high-risk devices.
  • Class III devices have the highest risk.

The IVD regulation has a similar classification system, from Class A (the lowest risk) to Class D (the highest risk).

Further examples for in vitro diagnostic Medical Devices are given in Figure 1, right panel.

Figure 1: Payne, Sara; Hall, Alison, What is the IVDR?, 2018 (Adapted from the MHRA (Medicines & Healthcare products Regulatory Agency)) handbook https://www.phgfoundation.org/briefing/what-is-the-ivdr


The higher the risk, the greater the regulatory obligations.  For instance, manufacturers of most implants under the MDR must supply together with the device:

  • An implant card with information for product identification: product name, serial number, code or batch number, unique device identifier, product model, address, and URL of the manufacturer.
  • Warnings, precautions, or measures to be taken by the patient or a healthcare professional regarding interference with external influences, medical examinations, or environmental conditions.
  • Information on the expected service life and any necessary follow-up.
  • Any information to ensure safe use of the product.

When developing a new Medical Device, it is essential to start by defining the use and specification of the device. This plays a key role in defining the class of the device, the design requirements and regulatory approval requirements. Where a device might fall under multiple risk classes, it is the highest risk class that applies.


[1] Payne, Sara; Hall, Alison, What is the IVDR?, 2018: https://www.phgfoundation.org/briefing/what-is-the-ivdr