I never had the opportunity to be involved in the FDA submission process, but from what I understand the FDA does not do any testing of their own. It's the companies responsibility to prove to the FDA that their device is safe and effective. All the testing is done by the device company, carefully documented, and then reviewed by the FDA. I've heard stories that the documentation for a class 3 medical device can be upwards of 20,000 pages which are all printed and handed to the FDA in 3 ring binders.
