[adevine]

It's interesting that the only test cleared is one for herpes. Conceptually, a finger prick sample would very clearly work for binary, "you've got it or you don't" tests, like STD tests (e.g. you've been able to buy home HIV tests for years that just require a few drops of blood from a finger).

Most blood tests, though, are about detecting whether levels of a substance are in a particular range - milligrams of cholesterol per deciliter of blood, mg glucose per deciliter, etc. Taking a much smaller sample is pretty much guaranteed to make the plus/minus error range larger, and capillary blood from a finger prick will have a greater percentage of contamination from intracellular fluid.

Even glucose meters you can use at home are much less accurate than glucose readings taken with a venous draw in a lab. In that case, the benefit to a diabetic of being able to do frequent home testing outweighs the loss of accuracy. If you're going to get work done by a lab, though, you are going to want it to be as accurate as possible, and in that scenario I don't see how a finger prick will be able to compare to a venous draw.