National Health Care Database
The problem with a national health database is "accuracy" and "context".
Accuracy. First, how does such a database intend to have a better track record than the national credit databases? My wife has, over the last several years been plagued with credit bureaus who have erroneously attached our home phone number to a bad loan of a woman with a similar name (middle name is different) and completely different social security number, of course. While we have been assured that the number will be taken out of the database, it persists all these years later. Similarly I have someone with a similar name that skipped out on a Discover card bill and I have been trying to get that off my record since we bought our house, 15 years ago! Personally, I don't want others data erroneously added to my records, nor do I want mine attached to others.
Context. In terms of context, the problem is that with records in the national database there will be situations where the entire relevant context will not be included with a particular entry. Let's say I am going to do charity work in some third world nation, and as a result get vaccinated for something important like Hep C (or similar). Or perhaps tested for it, before going. In the database goes that injection (or test). Five years hence my hopefully soon to be employer, with my permission runs a query of my national health records, looking for flags. Voila, Hep C transactions, typically indicative of high risk behaviors such as unprotected sex or intravenous drug use. Suddenly I am a potentially bad insurance risk and would cost the company more to insure than #2 on the list to hire. Not wanting to be illegal and discriminating for health issues, my formerly soon to be employer nit picks something else on my resume and moves to the next guy. So because I was doing wonderful work in a crappy part of the world, I have to start looking for a job again. That's all due to the missing context.