> we know conclusively that their goal is impossible
No we only know that their approach was wrong. Here is a preprint of a paper describing detection of 12 different types of cancer from a single drop of blood:
The problem isn’t the volume of blood, it’s that blood drawn from finger capillaries is not a representative sample for diagnostic purposes. There are plenty of tests that are even more sensitive, but they require a proper sample drawn directly from a vein or artery.
The problem isn’t the volume of blood, it’s that blood drawn from finger capillaries is not a representative sample for diagnostic purposes. There are plenty of tests that are even more sensitive, but they require a proper sample drawn directly from a vein or artery.