Re: Is there an opt out?
Is there an opt out?
How is this even allowed?!
This is the thing - as far as I can tell this is not even legal. First of all, medical data is classed as "sensitive" under UK DPA rules, so you should not have to opt OUT, they will have to get you to opt IN, and explicitly (so it can't be part of the small print in a contract, there must be a separate, explicit question if you want to permit this).
Secondly, it would be worth getting an opinion if sensitive data ought to be sharable without further consent - as far as I can tell there is a re-purposing involved here, which ought to have triggered a renewed request for your permission.
Oh, and before I forget, such a request much be coercion-free, so none of this "if you don't say yes, we won't be giving you your blood results" style "encouragement" that I've seen in various parts of the NHS.