Data feudalism and a hidden cost of an overbearing state

I was talking with one of my colleagues the other day: she's a medical statistician. She was justly pointing out the enormous cost of being required to obtain informed consent in statistical analyses of medical data.
The modern requirement is that, nearly always, one must obtain "informed consent" in order to include a patient in a study, even when such a study is merely follow-up, i.e. no experimentation will take place. The "cost" may be monetary in that the data is there but permission must be granted else the data will be destroyed (and the cost in man hours to obtain consent may be very large) or it may instead be the case that there is such a selection bias in the granting of consent (think of stroke victims, for example, where the most severely affected are unable to give consent) that the resulting data is so skewed as to be useless.
She felt very strongly that the impact on public health was intolerable.

Now I am not doctrinaire when it comes to the state: I feel it has its uses, and one of the most important (which tends to be forgotten) is in the area of public health. Most of the advances in human longevity stem not from medicine but from activities in the realm of public health. Inoculation is the one everyone will name, but I would go for clean water and sewerage. When everyone was fussing about Paula Radcliffe being caught short in the London marathon, I was shocked that she hadn't been arrested for defecating on the Public Highway.
But I digress. My point is that Public Health is an important state activity and I share my colleague's distress.
However, the state has brought it upon itself in my opinion.
Could one rely upon the British state to treat our personal data with circumspection, one might accept the absence of consent. Most of us would have forty years ago, I think.
But now we need to fight it all the way.
Why? Because the state sees our data as its property. MPs, the EU and the legal system constantly seek to share it far and wide.
Forty years ago the Inland Revenue was under tremendous constraints to keep our financial data private. It wasn't allowed to share that data with other government departments. Now it's a fast track to ministerial promotion to suggest ways to share our data with every Tom, Dick or identity thief. Even if ministers don't want to do it, the courts will. I think of the breach of trust that occurred over sperm donors. They were promised anonymity, come what may and then the courts turned 'round and said the rights of the child to know their biological parents overrode any commitments made to the donors. The courts have, moreover, failed to make the police destroy DNA and fingerprints taken from all those arrested, even where they weren't charged, let alone convicted.

The state increasingly seeks to own us by owning our data and it's essential that we fight it lest worse befall. It took about five years for the Nazis to take over in Germany. I wouldn't want them holding all my biometric data, would you?