Let’s talk about Essential Performance—the term that sounds like it belongs in a motivational poster but is actually a cornerstone of medical device compliance. If you’ve ever stared at a test plan wondering, “Do I really need to define this?”—this one’s for you.
What Is Essential Performance, Anyway?
According to AAMI CR500, Essential Performance is:
“Performance of a clinical function, other than related to BASIC SAFETY, where loss or degradation beyond the limits specified by the MANUFACTURER results in an unacceptable RISK.”
Translation? If your device stops doing something it’s supposed to do—and that failure could hurt someone—it’s probably Essential Performance.
It’s not about whether the device turns on or doesn’t electrocute anyone (that’s basic safety). It’s about whether it does its job in a way that keeps patients safe.
How Do You Decide What It Is?
Start with your Indications for Use. If your device is just along for the ride (think: adjunct therapy), you might not need to define Essential Performance. But if it’s delivering therapy or doing something critical—buckle up.
Then, do a risk assessment (hello, ISO 14971). Ask yourself:
• What are the clinical functions?
• What happens if they fail?
• Would that be bad? Like, really bad?
If the answer is yes, congrats—you’ve got Essential Performance.
Pro tip: Don’t get lazy with vague language. “Monitor alarms” doesn’t cut it if your device doesn’t even have alarms. FDA reviewers are not fans of generic fluff.
Common Pitfalls to Avoid
Let’s be honest—this is where things get messy. Here are some classic missteps we’ve seen:
• Skipping the risk analysis: You can’t just say “no Essential Performance” without backing it up. That’s like skipping the fire drill and hoping for the best.
• Using generic criteria: “Device functions as intended” is not a testable metric. Be specific. Be measurable.
• Copy-pasting from other devices: Just because it worked for Device A doesn’t mean it applies to Device B. Context matters.
• Assuming therapy = safety: Delivering therapy doesn’t automatically mean you’ve covered Essential Performance. You still need to define it.
• Ignoring the IFU: Your Indications for Use are the blueprint. If they say “delivers therapy,” you’re on the hook.
When You Can Say “No Essential Performance”
Yes, there are times when it’s okay to say your device doesn’t have Essential Performance. But only if:
• The IFU clearly shows it’s not delivering therapy.
• There are no clinical functions that could cause harm if they fail.
• You’ve documented this with a proper risk-based rationale.
No shortcuts. No, “we just decided not to.” And definitely no “we copied this from another device.”
Real-World Examples
- Thermometer – The importance of maintaining a certain accuracy is critical because if a fever goes undetected, then fever reducer would not be given, or the person may have a serious infection go undiagnosed and untreated.
- Infusion Pumps – Accuracy is extremely important. Administering too much or not enough of certain medications, such as Chemotherapy Drugs, can pose serious risks.
- UV light used to disinfect – If the UV level is too low, then there is the risk of the bacteria or pathogens not being killed and possibly being ingested. If the UV is too high, there is a risk of it burning a material and possibly putting toxic gases into the air.
These aren’t guesses—they’re tied to actual risk and clinical function.
Final Thoughts
Essential Performance isn’t just a checkbox—it’s a safety net. It’s how we ensure medical devices don’t just work, but work safely when it matters most.
So next time you write a test plan or prepare for a submission, ask yourself: What’s essential? Then prove it.
Do you have a device you’re unsure about? Do you need help defining Essential Performance criteria that won’t get flagged by reviewers? Reach out to our compliance team or submit a Contact Us form. We love a good challenge—and we’ve seen it all. Want us to feature your device in a future Tech Note? Let’s talk.