Providing clear traceability between design inputs and design outputs for medical devices can save a MedTech manufacturer from receiving negative observations on an FDA-483 inspectional observation form, investigators from the US Food and Drug Administration (FDA) remind industry.
“A common issue that we encounter [during inspections] is the lack of traceability between design inputs and design outputs,” said Mary Millner, a senior operations officer in the FDA’s Office of Medical Device and Radiological Health Inspectorate (OMDRHI), within the agency’s Office of Inspections and Investigations (OII). Design inputs “need to be complete, need to be unambiguous, and need to be verifiable. If a design input is not well written in the first place, is not clearly defined, or is otherwise ambiguous, it’s going to be very difficult for anyone to be able to demonstrate that the design input is verified.”
Millner, whose comments came during an “investigator insights” panel at MedCon 2025, noted that investigators also routinely encounter a lack of clear traceability documentation.
“The most common method of documenting traceability is through a design trace matrix, and during inspections I’ve encountered [situations where it’s obvious] that the manufacturer doesn’t have any sort of traceability or trace matrix documented at all, or the trace matrix is incomplete,” she said. “For example, they might be able to have documented traceability that a certain verification test was once completed for a design input, but it lacks the next step of demonstrating the traceability to the perspective design output, or vice versa.”
The bottom line? “Clear traceability between design inputs and design outputs has always been the expectation of the FDA, and it is also a requirement of ISO 13485,” Millner said. ISO 13485:2016 is the international quality systems standard published by the International Organization for Standardization (ISO).
Further, ensuring clear traceability in design documentation is of the utmost importance for device companies if they want to minimize their chances of receiving black marks during a facility inspection. Having complete documentation is helpful for investigators as they inspect and review records and is one way to minimize the amount of time an investigator spends at a manufacturing site.
“We cannot possibly cover an entire DHF [design history file] during an inspection [because] there’s just too much in there,” fellow OMDRHI Senior Operations Officer Tom Peter said during the MedCon panel discussion.
“Typically, what we’ll do is select some high-risk design requirements to focus on [by reviewing] your risk management file or some of the quality data that we’re reviewing during the inspection,” Peter explained. “We’ll select some requirements to focus on and having that trace matrix in front of us makes it so much easier to be able to trace through your DHF [and determine the] associated design outputs [and the] verification and validation activities that were performed associated with those requirements. That allows us to make very specific requests based on the references found in that trace matrix, as opposed to thumbing through a gigantic DHF.”
An inspection can move along at a brisker pace when manufacturers have their traceability ducks in a row, permitting investigators to move on to other topics and allowing company employees to get back to a typical day’s work.
After all, “we don’t want to be [at a facility] any longer than we have to be,” Peter said.
Tip: Trace Matrices Should Include ‘Pointers’ to Assist Investigators
Meanwhile, OMDRHI Consumer Safety Officer Laureen Geniusz told device manufacturers at the MedCon panel that including identifiers in a trace matrix – such as page or section numbers that point to specific requirements – is another way to keep an inspection rolling along.
“Many times, I’ll see in the verification or validation column that it only lists a report number and then says, ‘OK, we met that requirement, and here’s the report number,’” Geniusz said. “But some of these reports are so long that to try to find where it is addressed in the report can take a while. It is extremely helpful to get the good things faster, and what it also does is [provide] a great double check … to make sure that you did meet the requirement. So, if you just put pointers in there, that is very helpful.”
Tip: Don’t Retroactively Develop a DHF
The FDA’s Millner has inspected companies that failed to implement design controls in real time during a product’s design and development phase.
The agency’s expectation “is that as soon as a manufacturer decides that a design is going to be developed, that design control procedures are followed and a design plan is established,” she said. “However, I have encountered manufacturers – and these are usually smaller, less experienced manufacturers – that retrospectively create a design history file, either when the product is ready to go to the market or by putting together information for their 510(k) clearance, or even sometimes not until after they’re inspected for the first time.”
But at that point in the device development process, a company will more than likely discover that they don’t have the information their DHF demands – a potentially fatal oversight.
Tip: Remember to Transfer DHF After Purchasing 510(k)
Millner also pointed out that FDA investigators routinely uncover that manufacturers fail to have a device’s DHF transferred to them when they buy the product from another company.
“If you are purchasing a 510(k) from someone else, ultimately it is your responsibility to ensure that design control requirements are being met,” she said. “By not having that complete design history file, you’re not able to show that you’re in compliance with the Quality System Regulation. It’s also going to make it very challenging if you ever want to make a change to that device, to demonstrate that a new 510(k) submission is not required.”
[Editor’s Note: MedTech manufacturers can find themselves in hot water with FDA investigators if design controls aren’t up to par – but it doesn’t have to be that way. Give QualityHub a shout if your company needs assistance around design controls or other quality systems activities.]
