@AngleseyStick @DarkOptimism @goodlawproject yes, I'm pretty sure this is NHS England only.
It's still absolutely crazy though. And it's possible that it might include some data on Welsh patients who have been treated in England because of cross-border arrangements.
All supposedly anonymised, but put together a few medical conditions plus AI, join to one or two other databases (such as data harvested from social media) and deanonymising becomes fairly easy.