Right Decision Service standard operating proceduresFor this guidance a decision support system (DSS) is software that provides clinicians with knowledge and person-specific information to enhance decision-making in clinical workflows. These digital tools can be used across care settings, specialties, and pathways to support evidence-based decisions, improve healthcare delivery, and reduce errors.
When is a decision support system categorised as a medical device?
This guidance is for NHS Scotland organisations and partners, considering using the Right Decision Service (RDS) to deliver a decision support system. The guidance will help to determine if the decision support system may be a medical device. In addition to the guidance there is an interactive PowerPoint presentation which will guide you through the key considerations.
This guidance is based on the the current UK legislation The Medical Devices Regulations 2002 Statutory Instrument Number 618
It also refers to:
- Guidance on software as a medical device from the Medicines and Healthcare products Regulatory Agency (MHRA) based on this UK legislation.
- European Commission guidance Guidance document Medical Devices - Scope, field of application, definition - Qualification and Classification of stand alone software - MEDDEV 2.1/6 which the MHRA also references and is helpful in defining software as a medical device.
The majority of DSS hosted on the RDS are not medical devices. To be categorised as a medical device, a DSS must meet all the 4 specific criteria outlined in the test below.
- It is standalone software.
- It has a medical purpose.
- It performs an action on data other than storage, archiving, communication, ‘simple search1 or a verifiable calculation.
- It is for the benefit of individual patients.
[1] refers to the retrieval of records by matching record metadata against record search criteria (European Commission MEDDEV 2.1/6, 2016).
Software is a set of instructions that processes input data and creates output data (European Commission, 2016). A computer programme and a functional document such as a simple spreadsheet are both software. In the context of medical devices, standalone software is software that is not incorporated in a medical device at the time it is placed on the market or made available (European Commission, 2016)
A computer programme is a complete set of instructions written in a specific programming language that tells a computer what tasks to perform without the need to connect with or be hosted within another application. These instructions guide the computer’s behaviour, allowing it to execute various operations, solve problems, and interact with users or other systems. If the DSS is described as a “standalone software” or a “medical app” this would be indicative of it being a computer programme
A functional document is software that requires separate software, usually a general-purpose app such as Excel or a web browser, to perform its function. Examples include:
- A pdf that reproduces a treatment decision flow chart with logical links.
- Spread sheets - particularly if they provide complex functionality that is beyond that of existing paper charts e.g. an excel spreadsheet that calculates doses of a medication.
- Documents with macro or script enabled functions - complex medical applications can be written with languages such as visual basic
- Interactive web pages - these can utilise programming languages such as JavaScript to produce medical applications.
Functional documents are also standalone software.
For the DSS to be a medical device the manufacturer must intend for it to have a medical purpose as set out in the directive and the regulations. The intent is determined by what the manufacturer or developer states in the labels, promotional material and any instructions for use. The MHRA has included in their guidance (Medicines and Healthcare Products Regulatory Authority, 2023) more detail on each of the purposes set out in the directive and the regulations, pages 19-25. This includes terms such as:
- prevention of disease,
- diagnosis,
- monitoring, and
- treatment and alleviation.
The MHRA provides more specific guidance (Medicines and Healthcare Products Regulatory Authority, 2023) on what constitutes a medical purpose and what does not in relation to software. This guidance sets out that software that provides the following functions as not being a medical purpose
- Patient medical education
- Monitors fitness, health or wellbeing
- Offers lifestyle or treatment choices or referral advice
- Stores or transmits medical data without change
- Professional medical education
- An electronic record that replaces a paper version
- Software that is used to book an appointment, request a prescription or have a virtual consultation, if it only has an administrative function.
- Software that provides reference information to help a Healthcare Professional to use their knowledge to make a clinical decision.
- Databases without internal language/macros/scripting
The DSS must actively process data. Software that simply stores, archives or communicates data without performing any processing or change action on it will not be a medical device (European Commission, 2016)
The EU guidance (European Commission MEDDEV 2.1/6, 2016) states that a DSS could be a medical device if it performs the following actions on data:
- alters the representation of data for a medical purpose,
- provides interpretive search results, or
- it is intended to create or modify medical information.
Clinical calculators are not deemed to be medical devices where the calculation does not have an immediate medical purpose (e.g. statistical analysis) or can be easily verified (Medicines and Healthcare Products Regulatory Authority, 2023) for example:
- calculators without a medical purpose, eg statistical analysis
- simple scores, eg the ABCD2 score for transient ischemic attack, or
- simple calculations (addition, subtraction, multiplication or division), eg the Parkland formula for burns.
European guidance MEDDEV 2.1/6 (2016) states that “software for the benefit of individual patients is software intended to be used for the evaluation of patient data to support or influence medical care provided to that patient.
Examples of software which are not considered as being for the benefit of individual patients are those which aggregate population data., provide generic diagnostic or treatment pathways, scientific literature, medical atlases, models and templates, as well as software for epidemiological studies or registers.”
The following are examples of the types of DSS that may be medical devices:
- Systems that analyse patient medications to identify potential interactions, contraindications, or adverse effects. They provide alerts to clinicians when prescribing new drugs or systems that calculate drug dosages based on patient weight, age, and other parameters
- Systems that assist in diagnosing diseases based on patient symptoms, lab results, and medical history. For instance, systems that help interpret radiology images or pathology slides.
- Systems that perform calculations or other processing on data in a way that is not transparent to the clinician – so the calculation cannot be verified. Examples include integration of complex algorithms into patient record systems, and complex standalone calculators where the calculation cannot easily be checked manually – e.g. ASSIGN calculator; vancomycin prescribing calculator.
- Systems that predict patient risk (e.g., cardiovascular risk, sepsis risk) based on various factors, where the analysis or calculation is not transparent to the clinician and is too complex to replicate manually.
If the assessment of the DSS results in 4 ‘YES’ responses, it is likely that it will be considered a medical device and you would like the DSS to be hosted on the RDS website, contact the Right Decision Service Team for further advice. They can be contacted at his.decisionsupport@nhs.scot The team will discuss your proposal with you and provide further advice on how to proceed.