The article provides an overview of the provisions of a guidance document and highlights the key points to be taken into consideration by medical device manufacturers (software developers). 
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The Medical Device Coordination Group (MDCG), a voluntary association of national regulating authorities collaborating for further improvement of the medical devices regulatory framework, has published a guidance document dedicated to Medical Device Software (MDSW) – Hardware combinations.

In particular, the document describes MDSW intended to work in combination with hardware or hardware components.

It is important to mention that provisions of the document are non-binding in their legal nature, nor are they intended to introduce new rules or impose new obligations.

Moreover, recommendations provided in the guidance could be subject to changes, should such changes be reasonably necessary to reflect corresponding amendments to the existing legal framework.


Medical device software (MDSW) is widely used in the medical equipment ecosystem nowadays.

According to the guidance, approximately 25% of medical devices either include MDSW or are standalone MDSW systems. This surge is largely attributed to the use of smartphones and wearable tech, which often deploy diverse technologies to serve their designated functions.

This tech evolution has changed significantly the way patients and healthcare professionals interact with medical data.

As further explained by the MDCG, quite often in order for MDSW to function as intended, it needs to integrate with hardware or hardware components, such as sensors, that provide the necessary input data.

Wearable tech, such as smartwatches, bracelets, and virtual/augmented reality goggles, typically rely on this synergy.

These wearables collect data from hardware components including sensors and cameras, which feed into various MDSW platforms, including specialized MDSW applications (MDSW apps).

The document additionally emphasizes that some of these sensors or hardware components are intrinsic parts of mainstream consumer electronics, which are not initially related to the healthcare sphere.

The connection between the MDSW and these components raises questions about their categorization and the regulatory routes or conformity assessments required for them.

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Guidance Scope

These hardware components, through data and signals, are vitally important for the medical functionality of some MDSWs.

It is crucial to understand how MDSW manufacturers can show compliance with regulatory standards when the software and its associated hardware components are combined.

This document aims to clarify the regulatory implications when the hardware components (like cameras or sensors) are classified as medical devices or accessories to such devices.

It also describes situations where they are not considered either.

However, this guidance does not address the matters related to clinical evaluation or cybersecurity issues associated with these products, as these aspects are covered by separate guidance documents issued by the MDCG.

Interplay Between MDSW and Hardware Components

Numerous MDSW apps generate diagnostic or therapeutic information by processing data from hardware components.

These components can act as input sources and controls for the MDSW.

Such apps typically need a computing platform and energy source, often provided by devices like smartphones.

The effectiveness of these apps depends on the performance, accuracy, and reliability of their paired hardware components.

For clarity, the document provides a few scenarios as examples, namely:

  • Scenario A
    Consider a dermal patch embedded with a sensor.If both the hardware and the MDSW app are from the same manufacturer, then after purchasing the patch, users can download the MDSW app onto a smartphone.
    This app processes the data from the patch’s sensor, offering insights into physiological parameters, which can be shared with healthcare professionals.
    However, if the hardware and MDSW app are from different manufacturers, the process remains largely the same, but compatibility and data sharing dynamics might differ.
  • Scenario B
    In the case of a wearable, like a watch with an embedded sensor, the process is similar.
    If both the wearable and the app come from the same manufacturer, users can download or activate the MDSW app post-purchase.
    The app then processes physiological data from the wearable.However, if the wearable and MDSW apps have different manufacturers, users have the choice to download from a range of MDSW apps.
    Compatibility, data processing, and sharing mechanisms might vary based on the chosen app.

Regulatory Considerations

Article 2 of the MDR outlines that medical devices can operate independently or in conjunction with other devices or accessories.

From the scenarios above, it is clear that both MDSW and their paired hardware components need each other to serve a medical purpose.

Thus, for software to be classified as a medical device, manufacturers must define its medical purpose and subsequently prove its adherence to the MDR.

This includes ensuring that the interaction between the MDSW and hardware is safe and effective.

There are multiple ways these devices can be introduced to the market:

  1. The hardware component could be an accessory to the MDSW.
  2. The hardware might be classified as a medical device as part of a system, in combination with another device, or as an integral part of another device
  3. The hardware could be an inherent part of a consumer electronic not initially intended for medical purposes.

Market Placement

Options 1 and 2 above consider the MDSW and hardware as a medical device or accessory.

Therefore, MDSW manufacturers need to demonstrate MDR compliance, which includes meeting general safety and performance requirements.

Furthermore, the manufacturer must validate the safety, compatibility, and interoperability of the paired hardware.

If the hardware components are already compliant with the MDR, the MDSW manufacturer can leverage this compliance for validation.

For Option 3, where the hardware isn’t considered a medical device or accessory, the burden of the MDSW manufacturer will be to ensure the combined functionality of the software and hardware.

This involves monitoring, risk assessment, and mitigation to ensure the combined system’s safety and performance.


In summary, the document explains that as medical device software and hardware continue to integrate, it is vitally important to understand their interdependencies and the regulatory landscape governing them. This ensures that these combined systems not only serve their intended medical purposes but also maintain the highest standards of safety and efficacy.

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