Determining Essential Performance

Determining Essential Performance

 

In recent years, we have observed a growing emphasis from The US FDA on proper determination of Essential Performance (EP) for medical devices submitted for clearance. We have also noted that the increased emphasis on properly identifying Essential Performance has created some conflicts and challenges for clients, (e.g. They may believe they have no EP in their device, and the during the substantive review of a 510(k), the FDA disagrees and issues an AINN, stopping the review until EP is properly addressed). Thus, our clients have occasionally asked ERI Group for help in determining their essential performance characteristics.

 

The FDA requires a risk-based determination of EP and further indicates that EP must be maintained throughout the product life cycle. This is important. According to Intertek¹, designing your device using a risk-based model or hazard-based approach usually means that the device will be compliant with the required standards. This is the recommended approach.

 

This paper presents a methodical approach to determine device specific Essential Performance for a medical device. The Essential Performance analysis begins and ends with the client’s System Level Risk Analysis (RA), as those risks are generated for or from critical functions in the product specifications. It makes good sense that a detailed RA is done first, based upon intended use and indications for use of the product, prior to commencing design work. Starting the RA first is recommended. Note that the RA process may be iterative, as risks could be re-evaluated along the design flow so that, for example, an update to the Product Requirements may lead to newly discovered risks.

 

Essential Performance is determined from a risk-based approach to the device’s defined functions as guided by intended use and indications for use of the subject medical device. The following is a general method that ERI Group has used to define the Essential Performances of client’s medical devices.

 

To begin, ERI Group Regulatory team reviews the general, particular and collateral safety standards that apply to the client’s medical device in an effort to formulate initial EP. These are the most common basic safety and risk management standards to consider for electrically operated medical devices:

• IEC 60601-1: General requirements for basic safety and essential performance of medical electrical equipment
• IEC 60601-1-2 Basic safety related to EMC (electromagnetic disturbances
• IEC 60601-1-X designate Collateral standards that define the requirements for certain aspects of performance and safety. Collateral standards may amend or modify 60601-1 requirements.
• IEC 60601-2- X designate Particular standards that are device specific, and define the requirements for or data measurements built into a client’s medical device
• ISO 14971:2012 – Application of Risk Management to Medical Devices

 

There are many other important documents such as but not limited to:

• 10993 series for dealing with Human Contact devices
• 62304 software lifecycle for software management, including risk.

However, the basic methods for risk-based determination of essential performance apply to most all risk analyses methods, thus the determination of EP is similar for medical devices where you are working with biological attributes, electrical performance, or software.

 

Electrical Standards EP Review: IEC 60601-1:2005 (Third Edition) offers the following definition of Essential performance as:

“Performance of a clinical function, other than that related to basic safety, where loss or degradation beyond the limits specified by the manufacturer results in an unacceptable risk.”

The standard also notes that “essential performance exists when the feature or function in question is either absent or its characteristics are degraded to a point that the ME equipment is no longer suitable for its intended use.”

We conclude that General Essential Performance guidance from the standards is determined to be:

“Performance necessary to achieve freedom from unacceptable risk and ability to maintain performance in the intended use of a clinical (or critical) function, other than that related to basic safety, where loss or degradation beyond the limits specified by the manufacturer results in an unacceptable risk.”

 

Determining Specific EP for your Medical Device: No specific EP guidance is available, as EP is uniquely determined for each medical device. We see from a review of the 60601 basic safety standards that the specific risks identified as having EP are ultimately up to the manufacturer to define. As guidance, we point out that not all performance functions listed in the Risk Analysis will be considered as EP, however, any performance function that leads to an unacceptable risk per the Risk Analysis is EP.  It is noted that EP requirements for Particular and Collateral standards frequently identify specific Essential Performance within. Thus, it is important to browse the titles and document scopes of the applicable Particular and Collateral standards for specific EP considerations.

 

This process starts with the complete RA, and funnels down to just the few remaining risks that are not mitigated by safety, clinical, or bench testing. The remaining risks are candidates for the system EP. These include those risks that have a high enough probability of occurrence that analysis could lead to an unacceptable risk under certain conditions.

The risk item reduction to EP candidates proceeds as follows:

1. Start with a working copy of the complete Risk Analysis (RA), Remove all non-clinical RA functions – this includes bench tests and standards tests.
2. Eliminate all functions/risks not tied to the intended use or indications for use (thus, not EP)
3. Eliminate all RA items not applicable to this device version. Remove all risks associated with out-of-scope features for this version of the device & RA. (i.e. subject device version has no human contact, or no wireless data transmission)
4. Determine if the loss/degradation of remaining functions leads to unacceptable risk

 For all functions where loss or degradation leads to unacceptable risk Essential Performance is the performance necessary to keep the risk acceptable.

[1] Intertek Knowledge and Education Paper – Top Ten Reasons Products Fail Compliance Testing & Certification, Dec, 2022.

Connect with us to learn more about our Essential Performance expertise for medical device companies at regulatory@erigroup.com