Welcome to the Mindset Extended Reality (XR) for digital mental health programme learning resources, which include three series: medical regulation, clinical evidence and lived experience involvement. Mindset-XR is helping to catalyse the growth of immersive digital mental health solutions in the UK, through funding, tailored support and training. It is delivered by Innovate UK and the Health Innovation Network South London (HIN).
This series focuses on medical regulation, with key insights from Hardian Health. Across 10 modules, we provide an accessible introduction to people and companies that want to learn more about medical device regulation, with a focus on XR devices. Each module offers a high level overview of a different topic, including medical device regulation in the UK and EU, core medical device standards and overseas regulation. Each module includes additional resources to support your learning and a quiz to test your understanding.
Outline
Welcome to Module 3: How are medical devices classified? In this section, we’re exploring different classification definitions of medical devices. We will also look at software as a medical device, accessories and how these all fit into the EU MDR classification rules. Topics include:
What are the classifications of medical devices?
The different medical device classifications and how they’re defined.
How is risk classified for medical devices?
How risk is measured and classified for medical devices.
What is the difference between medical devices and accessories?
Some common examples of medical devices and accessories to medical devices.
Multiple choice questions to test your understanding on medical device classifications.
What are the classifications of medical devices?
There are a number of different abbreviations you will hear about which all are regulated medical devices. These include:
- Software as a medical device (SaMD)
Intended to be used for one or more medical purposes that perform these purposes without being part of a hardware medical device.
- Software in a Medical Device (SiMD)
Incorporated that is typically incorporated into a physical medical device to control its performance or provide specific functions.
- Medical Device Software (MDSW)
Intended to be used (alone or in combination) for any of the purposes described in the definition of a âmedical deviceâ, as per EU Medical Device Regulations.
- Programmable Electrical Medical Systems (PEMS)
Software, firmware and equipment that can be programmed to carry out functions that aid medical care or treatment.
PEMS
These are devices which consist of software, firmware, and equipment that can be programmed to carry out functions that aid medical care or treatment. These are often combined with SaMD or AIaMD for data collection. Questions to consider include:
Is there a physical element to your device e.g. powered data collection tool?
Even if you buy in the physical part of your SaMD from another manufacturer, if your name is on the packaging and it is to be used in conjunction with your product you are the legal manufacturer therefore take responsibility in its regulatory compliance.
What additional requirements are there for a PEMS?
Electrical and mechanical safety testing, Electromagnetic compatibility and compliance to standards such as EN 60601-1 Medical Electrical Equipment, Biocompatibility, RF testing where applicable etc.
How is risk classified for medical devices?
The risk classification of a medical device describes the level of risk to a patient when this device is used.
Risk classification categories
Medical devices under UK Medical Device Regulations (MDR) 2002 and EU Medical Device Regulations (EU MDR) fall into four different risk classifications. Class I is the lowest risk of the device and Class III is the highest risk.
This rating system helps to identify the appropriate risk classification for your device, which is based on both the significance of information provided (i.e. treating/diagnosis, driving clinical management or informing clinical management) and the state of the healthcare situation or patient condition (Critical, Serious, Non-Serious).
Class I
The medical device is for a non-serious situation or patient condition and provides low levels of information for clinical management.
Class IIa
The medical device is for a non-serious or serious situation or patient condition and provides low or medium levels of information for clinical management.
Class IIb
The medical device is for a serious or critical situation or patient condition and provides medium or high levels of information for clinical management.
Class III
The medical device is for a critical situation or patient condition and provides high levels of information for clinical management.
Importantly, most SaMD that may be a Class I under UK MDR will fall under Class IIa or above under EU MDR. In addition, it is important to note that whilst Class I devices can self-certify, Class IIa and above must undergo a notified/certified body audit prior to going on market. Â
Selecting the correct risk classification for your device
When finding your risk classification, you need to ask yourself what is your software doing:Â
Directly treating, diagnosing or detecting a disease
Does your software/AI device directly impact a patient or the diagnostic capabilities of healthcare professionals?
Driving clinical management
Does your device give information that is then later used to drive further diagnostic tests, treatments or investigation decisions?
Informing clinical management
Does your device give non-urgent clinical information either by aggregating data or by informing future options for treatment, investigation and diagnosis?
Then, you need to consider how critical the clinical condition is where your software is deployed:
Critical
Situations where a time-sensitive response is needed to avoid long-term disability, death or serious deterioration. The disease state is life-threatening.
Serious
Situations where the software functioning properly is vital to avoid unnecessary interventions or tests. The disease state is moderate and may not require major interventions.
Non-serious
Situations that are not time critical, but where accurate diagnosis and treatment are still important. The disease state is usually chronic, mild and predictable.
So you can see if your device is diagnosing a critical condition, such as the diagnosis of a heart attack, your device will likely be a Class III device because of the significance of the information and the state of the healthcare condition. Whereas informing the clinical management of a lower risk condition, will result in a lower risk classification. Â
EU Medical Device Regulation (MDR) Rule 11
EU MDR Rule 11 provides guidance on the risk classification for software specifically.
All software starts at a Class I, but then follows a flow for up-classification.
Firstly, if your software monitors vital physiological processes it becomes a Class IIa device, and a Class IIb device if it monitors vital physiological processes where if incorrect, the patient could be in immediate danger.
Secondly if your software provides information used to take decisions with diagnosis or therapy it becomes a class IIa device.
If we keep working through the rule, if the decision can cause serious deterioration in health or require surgical intervention, it becomes a class IIb device, and if its impact can cause death or irreversible deterioration, it is then a Class III device, the highest risk.
What are the differences between medical devices and accessories?
Now that you know how to classify devices, let’s have a look at the differences between medical devices and accessories to medical devices:
Medical device examples
Traditional examples of medical devices that you may know include things like pacemakers, stents and valves used in surgeries. Some more modern SaMD examples could include image triage platforms, image segmentation platforms (e.g. detecting pneumonia on a chest x-ray), or even a cognitive behavioural therapy application.
Some modern hardware examples include the arrhythmia detection app on an apple watch or robot arms which assist in surgery.
As you can see, there are a wide variety of possibilities when it comes to medical devices but they all have one thing in common. They are all products or equipment which are intended to be used for a medical purpose.
Have a look back at Module 2 if you want some more information on whether or not you are building a medical device.
Accessories: definition and examples
- An accessory is not a medical device itself but is intended by its manufacturer to be used with one or more specific
medical devices.
- Its purpose is to enable or assist the medical device(s) to function as intended.
- Accessories shall not act by pharmacological, immunological, or metabolic means as medical devices do.
An example of this could be software which is designed to process and display data from a continuous blood glucose monitor.
The software itself is not doing anything other than being used to enable the blood glucose monitor to be used effectively by providing necessary data interpretation.
Summary
In this module, How are medical devices classified?, we explored the different classification definitions of medical devices. We also explored how software as a medical device and accessories fit into the EU MDR classification rules. After using this resource, you should have a understanding of the following:
Depending on how your device is meant to function it could be SaMD, SiMD, MDSW or PEMS, or a combination of the above.
Under EU MDR Rule 11, most SaMD is Class IIa or above.
Some SaMD have a physical component (PEMS) which also needs to be regulated.
Accessories are not medical devices themselves, but are intended to enable or assist a medical device to function.
Quiz
Got questions, comments or feedback?Get in touch with the teamhin.mindset@nhs.net | joe@hardianhealth.com
PowerPoint: How are medical devices classified? – click to download
Next module – Module 4: What is quality assurance?
Back to Module 2: What is a medical device?