Standards are necessary for the better functioning and regulation of different manufacturing and industrial sectors. And when it comes to the healthcare sector, their importance increases to a thousand folds.
IEC 62366 is also one of such standards. Devised by IEC, this standard is divided into two parts. Part one of this standard aims to regulate the application of usability engineering to medical devices whereas its second part assists manufacturers in complying with the requirements of part 1 of this standard.
Standard Specification & Composition
Title of the Standard
IEC 62336 is divided into the following two parts:
- IEC 62366-1:2015 – Medical devices – Part 1: Application of usability engineering to medical devices.
- IEC/TR 62336-2:2016 – Medical Devices – Part 2: Guidance on the application of usability engineering to medical devices.
Scope of the Standard
The standard defines a process through which a manufacturer can analyse, specify, develop, and evaluate the usability of a medical device with relation to safety. This process helps the manufacturer to analyze and reduce the risks that are associated with the normal use of the medical device. This standard also enables the manufacturer to identify the risks associated with the abnormal use of the device. However, this standard is unable to analyze or reduce such risks.
IEC 62366-Part 1
Part 1 of IEC 62366 has cancelled and replaced the first version of IEC 62366 and it’s Amendment-1. Both of these were published in 2007 and 2014 respectively. The updated version of part 1 of the standard now contains contemporary concepts related to usability engineering.
IEC 62336-Part 2
Part 2 of the standard contains tutorials that help manufacturers in complying with the requirements of part 1. It also offers detailed descriptions in terms of usability engineering methods. These methods can be applied to medical devices beyond their safety-related aspects of user interfaces.
IEC 62336-1 & Risk Management
Part 1 of IEC 62366 shows strong adherence to ISO 14971:2007 and other methods related to risk management as they are applied to safety-related aspects of medical device user interfaces.
Usability Engineering & IEC 62366
BSI define usability as
“A multi-dimensional quality that refers to the ability of human to interact easily and relatively error-free with a system or product.”
The impact of usability is evident in the healthcare system and medical devices. Chances for errors are high for a medical device that lacks usability. This lack of usability can also lead to the device not being used as intended. All of these shortcomings delay the delivery of therapy either partially or completely, hence putting the patient’s safety in danger.
Steps Involved in the Usability Engineering Process as per IEC 62336-1
Steps of Usability Engineering Process requires following from the manufacturer
Hazard Deduction through Real-use Scenarios and Risk Assessment (Step-1)
Use Specification
Provision of a Usability Engineering File (UEF) for the medical device which will contain:
- Use specification of medical device in usability engineering;
- Intended medical use and intended medical indication;
- Patient and user groups;
- Use environment and functionality; this includes physical principle and technical structure and
- Application of the medical device i.e. part of the body or type of tissue to which the device will be applied.
Characteristics Related to Safety
- Identification of characteristics related to safety and usability as part of risk analysis.
Identification of Known, Foreseeable Hazards, and Hazardous Situations
- Determining the severity of a possible harm.
Use Scenarios
- Involving user interaction along with documentation on UEF.
- Identification of hazard related real-use scenarios;
- Identification of safety characteristics related to User Interface and Use Errors.
Controlling Risks with User Interface Design (Step-2)
Following measures are involved in risk control with user interface design
Specifications for User Interface
User interface specification is derived from usability verification which itself is derived from the following:
- Use specification;
- Known or foreseeable use errors associated with medical device and
- Hazard-related use scenarios.
Specifications for User Requirements
- They provide requirements for user interface design.
Evaluation Plans
- They describe the process of exploring and evaluating user interface design.
Using Usability Engineering to Design User Interface
- Usability engineering methods will be used in designing and implementation of the user interface.
Risk Evaluation.
Risk Control Analysis
- Performing a risk control analysis to define appropriate risk control measures that will help in risk reduction.
Risk Management through Formative & Summative Evaluation (Step-3)
Formative Evaluation:
The manufacturer performs formative evaluation until all use-related risks are appropriately controlled. This evaluation should be performed in such a way that no need remains for refining the user interface further.
Summative Evaluation:
The manufacturer performs summative evaluation so that the development of the user interface gets completed. The summative evaluation demonstrates that the user interface is safe to use.
Risk Evaluation & Risk Control (Step-4)
This step involves the following procedures:
- Evaluating residual risks using risk management plan’s criteria.
- Evaluating the effects of risk control measures.
- Ensuring that all potential risks which may arise from the identified hazardous sources have been brought into consideration.
Follow-up Procedures
After the manufacturer has implemented the usability and fulfilled all the requirements, he can follow certain procedures to keep a check on usability process. These procedures are:
- General Examination.
- Verification: This procedure determines whether the manufacturer has fulfilled specific product requirements or not.
- Validation: This process ensures that if a specific user can get access to the intended use of the medical device through a specific use context.
The manufacturer can decide to carry out these follow-up procedures either with the help of an automated computer process or by a professional.
Changes and Amendments in Made in IEC 62336-1
Many changes and amendments have been made in IEC 62366-1:2015 – Medical devices – Part 1: Application of usability engineering to medical devices. All of these changes have been published in June 2020.
Main Changes Made in IEC 62336-1
Following are the primary change made in updated version of IEC 623336
Reference to ISO 14971
Manufacturers will now refer to ISO 14971:2019 instead of ISO 14971:2007 while referencing to risk management requirements of IEC 62336-1’s updated version.
Inclusion of Definitions
- Use Scenario (Definition-3.2.2)
This term defines use error which can result in significant harm. It is well-aligned with the term “Critical Task” which is used in US FDA.
- User Group (Definition-3.25)
This definition has been rewritten in the updated version of IEC 62336-1. It defines user group as a subset of users, whose interactions with the medical device are influenced by certain factors such as professional status and disease type.
Types of Use in Accordance with ISO 14971 & IEC 62336
The updated version contains the following Type of Use; reasonably foreseeable misuse and not reasonably foreseeable misuse.
Reasonably Foreseeable Misuse
Reasonably Foreseeable Misuse is divided into normal and abnormal misuse. Although abnormal misuse is not included in the scope of IEC 62336, it is included in the scope of ISO 14971. As for the normal use, it is further divided into correct use and uses error.
Both ISO 14971 and IEC 62336 are checked for their correspondence with the type of use. They are then applied accordingly.
Risk Control Measures (Section-4.1.2)
This section now contains training as a third priority control measure with safety information.
Requirements for Summative Evaluation (Section-5.7.3)
This section contains new requirements regarding summative evaluation. These requirements:
- Explain the role of participants who are involved in the summative evaluation as representatives of intended user profiles;
- Explain the role of the test environment and use conditions as representatives of intended use environments;
- Describe correct use for each use scenario which is related to hazard and
- Describe data collection during the test.
Acceptance Criteria for Summative Evaluation (Subclause-5.7.3)
This clause has been omitted and replaced by a clarification. This clarification states the purpose of summative evaluation, which is to collect objective evidence that renders use-related risk acceptable.
The updated version also contains an additional requirement regarding correct use for each use-related scenario. Now, both the success and failure of summative evaluation are dependent upon the extent up to which use-related risks are avoided.
Physical Mismatch
The term physical mismatch has replaced the term “Action Errors” which was used in the previous version of the standard. The term action error described a use-error that resulted due to physical limitations while performing a task.
Conversely, the term “Physical Mismatch” is slightly different from “Physical Actions” used in US FDA. This term highlights the contrast present between capabilities that are required for performing a task against the physical capabilities of the user.
TS Q & E can support Companies as per IEC 623666
TS Q & E has a team of engineers and experts having an extensive experience in dealing with IEC 62366 and medical devices. For companies, it would be difficult to understand each and every requirement of the standard. Therefore at this point, the experienced consultants who are already working for these standards for their multiple clients can actually help to better achieve compliance requirements.
So if you need any support in implementation of IEC 62366 for your products, you can inquire us at our Inquiry/Contact Us page.
