Time, skill required and volume are all in favor of the finger prick method. And some people absolutely freak out about needles but would be ok with a finger prick.
> Time, skill required and volume are all in favor of the finger prick method. And some people absolutely freak out about needles but would be ok with a finger prick.
Except the pain factor. Finger pricks are actually more painful, particularly when you have to draw more than a single drop of blood. Your fingers have more nerve endings than your upper arm. Also, you tend to use your fingers more than you apply pressure to your upper arm (e.g., typing, using your phone, playing the guitar - all of those require applying pressure to your fingertips, which will hurt).
Even diabetics oftentimes prefer to use the arm pricks, and they need to draw a lot less blood than more elaborate tests need. (Not all diabetics, but enough that there are literally blood glucose monitors that advertise this as a specific feature).
Not disagreeing with you, just saying the finger prick has a lot going for it. In particular the lower skill barrier to do it may make it cheaper or more convenient.
It certainly opens the possibility of self administration up a lot more than a needle.
The problem with self-administration though is misinterpretation. Not to mention that the logic of cheapness/convenience -> more data -> better health doesn't always hold. The more features you screen for the higher the chance of false positives, and most people don't know how to put correct readings into medical context.
All of what you say are true - phlebotomy requires actual skill (try getting blood drawn by a trainee!)
But... I grew up absolutely fearing and hating the finger prick thing the pediatrician would use. I remember getting all sorts of other scrapes and cuts that bled and wondering why they hurt so much less than that thing. From a practical perspective, if I knew a test involved that (rather than an arm draw), I'd delay and avoid it because of the pain.
Flip side of that is a friend of mine who we could make pass out by having a conversation about needles. I would go for the finger, personally, but the least painful/anxiety inducing method would probably be the best choice.
I don't know what they're screening for, exactly, but there are people who live remote without immediate access to medical care. If they could do this prior to an office visit that may help. It opens possibilities that aren't already, and that's just in the context of the US. Think aid workers around the world, that would have to be easier than maintaining needle hygiene.
