ISO 14971:2019: Criteria for overall residual risk

[Aikendrum]

Some potential guidelines:

The longer the type of device (and its underlying interaction with human physiology) has been in practice, then it is more typical that a family of similar products has less tolerance for risk. That is: more of the risk space is unacceptable.

If there are alternative treatment options to the underlying technology used for physiological interaction with the patient, A new family of products using the alternative approach to treatment should NOT accept risks at a higher rate than the competing technology. Nobody should let you market a fancy new hospital bed if it could electrically shock people or pinch them, no matter how many USB ports you include (for example).

If the medical outcomes are particularly poor in the absence of the device (or alternative treatments), then it is typical that the new product family will be more accepting of higher risks.

If the family of products will be used in limited circumstances with a well-understood group of users (because of the nature of the device) it is more typical that there is a tolerance for higher risks when compared to a medical device that could be used by almost anyone almost anywhere. Compare dental x-ray device with toothbrush. Both need to be safe, but there are acceptable risks with an X-ray machine that would never be accepted with a toothbrush.

At the very least, you can use the collected data to show that as far as risk tolerance you are aligned with, or better than what is on the market (or in medical use).

Thank you, this was super helpful. I think I'm on the road now.... now I just need to figure out how to dovetail the review to inform risk management, with the review done for a Clinical Evaluation Report to avoid doubling up!

 

[Tidge]

Given the current 'state of the art' with respect to Risk Management and Notified Bodies, don't be surprised if you find yourself 'doubling up'. I have complained (often, loudly) about being required by (NB auditors) to perform 'risk control option analysis' line-by-line in documents subordinate to a Hazard Analysis (even if those documents don't explicitly examine risk, such as FMEA).

On the topic of establishing 'overall risk acceptability', I no longer see what value the exercise brings if the enforcement of the standard (14971) requires all risks to be minimized (beyond just being individually analyzed). I suppose that this exercise (which is done independent of particular design choices) could provide a small amount of wiggle room in the area of (eventual) disclosure of residual risks, but that isn't my sense of the current state of affairs. From my PoV it appears that the NBs and/or regulators simply don't trust medical device manufacturers to implement the RM activities 'up front' and are instead insisting on post-implementation analysis and attestation... which is IMO an example of a reactionary approach (in the capability maturity model of organizations).

 

[LEMAB]

Hi All

Per ISO14971:2019; the manufacturer must document the method and criteria for overall residual risk evaluation in the Risk management plan.

I am wondering if you have any idea what could be some possible method and criteria for overall residual risk evaluation.

I am slightly confused by difference between method and criteria.

if i say my criteria is :" " The overall residual risk level is acceptable if all individual risks are determined to be acceptable i.e. after all individual risks have been mitigated to acceptable levels or determined to be acceptable through the BRA analysis."

Then is my method just : "checking all residual risks in my risk files and confirming all risks are acceptable"?

Thank you

Mithilesh P.

I would recommend you to read the ISO/TR 24971 which is a Guide. They give you some ideas on the "method" to use in point 8 8. There it says that even if all the individual risks are acceptable, may be some or many of them are "close" to the limits, so they need to be further investigated. And this guide gives you some approaches.