Toby,

I ran across your inquiry.  If you are still looking into this topic, InterSystems listed as a special class of medical devices called an MDDS (medical device data system).  If you fall into this category of usage it is fairly straight forward, and even if you don't, registering as a Class I device is very manageable if you are registering as a know class or device capability.

There is still a number of confusion forms and it never hurts to have some expert guidance on filling things out correctly.  We used a company called Emergo to help us with the paperwork.  They are knowledgeable and affordable.