I would be comfortable sharing my data (for the greater good) if I had a
ironclad guarantee -- that I could believe -- that it wouldn't be used against me.
The U.S. is nowhere near that. So, no data for collective you -- except when you rip it from my fear-clenched hands, regardless.
Think I'm speaking in the abstract? In my 20's -- a few decades ago -- I had to purchase individual insurance. I had one -- one -- appointment with a psychologist in the prior two years of medical history then requested. A "touchbase" from some childhood counseling.
Fortunately, a friend of a friend was able to "unofficially" run my insurance application by the underwriting team. If it had been "officially" processed, the result would have ended up in a shared database of application results. (Yes, the insurance companies in the U.S. have long shared their underwriting decisions with each other -- surprise!)
The word back on my application: Denied! Why? (Again, I had an inside track on the process not normally available to the applicant.) Because of that one -- one -- counseling visit, in isolation and with no attendant diagnosis.
I learned my lesson. I will never share such data, that can be used against me, without ironclad assurances. And, as the past couple of decades' experience, both direct and learning by reading and observing the news and other cases, have taught me, such assurance is pretty much impossible to achieve -- even commitments made in law are taken back as soon as power shifts.
The one hope for this changing that I see? Universal health care coverage. Because then, at a societal level, you are covered regardless. Your individual history no longer plays a role in whether you are covered.
I hope that the logical, scientific side of medical science starts to see things this way: That the future, expansion, and greater facility and efficacy of their work, depends on it.