With the implementation of the EU MDR regulation, the risk management process is becoming increasingly interconnected with other essential processes of medical devices (e.g., design and development, clinical evaluation, post-market surveillance, etc.), and ISO TR 24971 is a valuable tool for using risk management processes to improve the quality, safety and effectiveness of medical devices and is seen as a guide for the implementation of ISO 14971:2019.
This issue will delve into ISO TR 24971 and highlight the key requirements and methods for the implementation of an effective risk management process that complies with quality management system regulations (e.g. ISO CFR 820) and relevant applicable regulatory requirements (e.g. EU MDR).
Description of intended use.
Safety-related characteristics of medical devices.
Identify the hazards and hazards associated with medical devices.
Assess risks and dangerous situations.
The description of the medical device should include the relevant content of "reasonably foreseeable identification of misuse".
Misuse is defined as "the use of a medical device in a manner not intended by the manufacturer, but which may be caused by human behavior" and may be related to misuse, specific misuse, or intentional use of a medical device for other medical purposes, such as exceeding its intended use.
Misuse can be caused by different reasons, such as poor risk perception and unclear instructions for use.
To help manufacturers identify equipment characteristics in hazardous situations, ISO TR 24971 provides a complete list of issues in Annex A to support the identification of equipment characteristics that may affect safety.
Identifying hazards is the first step in the risk analysis process. Hazards are potential sources of harm and may be related to the use of the medical device or the product itself (design).
Typically, medical devices only cause or result in injury when a series of events occur that result in a dangerous situation.
Dangerous situations related to failures, the following different scenarios can be envisaged:
However, a hazardous situation may also occur when there is no failure or when there may be an intrinsic connection to a specific medical device**.
1.Each identified risk needs to be evaluated based on a ranking of specific risks, which is as follows:
the probability of the injury occurring;
The severity of the injury.
2.Two different methods can be used to estimate the probability of occurrence: quantitative and qualitative. Quantitative methods should be used when there are sufficient data and confidence to estimate the probability of harm occurring. Otherwise, qualitative methods are more reliable than quantitative methods with high uncertainty.
A high degree of attention should be paid to situations where the probability of occurrence cannot be estimated, such as software failures or misuse.
When it is not possible to estimate the probability of an injury, it is necessary to assess the risk based solely on the severity of the injury.
February** Dynamic Incentive Plan 6. ISO TR 24971 Risk Control StrategyWhen implementing risk control measures, prioritization is crucial.
For an overview of risk control options, see the following scenarios:
1.The assessment of the overall residual risk is an important moment in the risk management process, including the overall residual risk assessment, i.e., the risk after the implementation of risk control measures.
2.ISO TR 24971 provides different inputs that can be used as a starting point for assessing residual risks (including but not limited to the following):
Different sequences of events may lead to different hazard situations and risks, each of which leads to an overall residual risk;
Specific injuries can arise from different hazard situations;
A thorough review of all operating instructions for medical devices may reveal inconsistencies or difficulty in following instructions.
3.ISO TR 24971 lists examples of different methods for residual risk assessment:
Weigh the benefits associated with the intended use of the medical device against the overall residual risk;
a visual representation of residual risk;
Comparison with similar medical devices available on the market;
Hear from experts to support the overall residual risk assessment related to the expected benefits of the medical device.
Note: It is not possible to add up all the individual residual risks in a way that can be used for the overall residual risk assessment. There is no preferred method for assessing the overall residual risk, and it is the responsibility of the manufacturer to determine the appropriate method.