alot of people think that health records cant be decentralised because there is so much data and it just cant fit on a blockchain.
this is because most people only see the data within a blockchain in the format of a financial transaction:
[in: 1Fr0m4p3r50n value: 0.01btc]
[out: 1t04p3r50n value: 0.01btc]
[signed: 1Fr0m4p3r50n5sign4tur3]
now imagine
[Doctor: 1Fr0m4p3r50n patient: 1t04p3r50n symptom: insomnia result: yes]
[signed: 1Fr0m4p3r50n5sign4tur3]
[Doctor: 1Fr0m4p3r50n patient: 1t04p3r50n symptom: pregnant result: yes]
[signed: 1Fr0m4p3r50n5sign4tur3]
[Doctor: 1Fr0m4p3r50n patient: 1t04p3r50n symptom: HIV result: no]
[signed: 1Fr0m4p3r50n5sign4tur3]
Yeah an imaging report would never fit on the blockchain. IPFS is a good solution for this though. We can just store simple referents to the data on chain and store the vast bulk of information in IPFS.