Many device programs treat manufacturing readiness as a single milestone. In practice, there are two points where a structured review prevents expensive surprises: before the design verification build, and before full-scale manufacturing begins. Each one answers a different question.
Before the design verification build
The first review confirms that the manufacturing processes are correct before units are built for design verification testing. It also looks for issues that could cause test failures or make it hard to scale manufacturing later.
This matters because design verification units have to represent the final product. When units are built on processes that are still unstable, a test failure can trace back to how the units were made, and sorting that out takes time. If the process changes after verification, some of the testing may need to be repeated.
The review starts with the critical characteristics. Engineering builds should show that the process can hold them consistently, with data from enough parts to be meaningful.
It then looks at equipment and fixtures. They should be close enough to the production versions that the units built for testing represent what production will make.
Test and inspection methods need to be validated before they are used to judge verification units. A method that cannot repeat its own results can fail good units or pass bad ones.
Materials and components should come from the intended production suppliers wherever possible. A switch to a new supplier after verification can bring new testing with it.
Finally, the review flags steps that will be hard to scale, such as manual operations, long cycle times, or operations that depend on one skilled person. These are much easier to address before verification than after.
Before full-scale manufacturing
The second review comes before full-scale manufacturing begins. Its purpose is to verify that yields, costs, and throughput match expectations and that all process controls are in place.
Yield from pilot and validation lots should be compared with the yield assumed in the cost model. A gap of a few points changes the cost per unit and the capacity of the line.
Cost per unit should be rebuilt from actual yields, cycle times, and material costs, then compared with the target.
Throughput at the bottleneck step should be compared with the demand plan, including the shifts and staffing needed to meet it.
Process controls should be implemented and working. That includes control plans, in-process inspection, nonconformance handling, and training records for every operator on the line.
What each review produces
Both reviews end the same way: a list of gaps ranked by risk, each with an owner and a date, and a recommendation on whether the program is ready for the next step.
What investors should ask
For a company approaching design verification, ask whether the processes were reviewed before the build and what was still open. For a company approaching launch, ask whether yields, costs, and throughput have been confirmed on the floor or are still model assumptions. The answers say a lot about how firm the launch plan and the margin targets are.
Which of these two reviews have you seen skipped more often?
Chris Steadham is the founder and principal of Truestead Advisors and has spent 30+ years in medical device product development, manufacturing scale-up and general management. Preparing for a design verification build or a production launch? Start a conversation.