The regulatory agencies require a "quantitative" method to determine donor qualification for donors who will donate RBCs via automation (i.e. an actual hgb/ hct value). For platelet/ plasma donors... they can use a "qualitative" method (ie CuSO4). Plain and simple - it is not required. It is usually required as a variable to program the instrument, the more accurate, the better the product results. But, it is not required by regulatory agencies. It's not necessarily that they're "cheap"; it's the question of what you do with the information once you get it. The donor had to qualify to donate (12.5% hgb/ 38% hct). A level slightly below that (to account for variations in venous vs. capillary sample, and possible poor technique, is still not going to be enough to make a donor "anemic". That is why the acceptance criteria is as high as it is... a Hct of <38% is not the criteria for a diagnosis of "anemia" A few years ago, there was some regulatory push back that if you get that Hgb/Hct result, and it turns out that the donor did not qualify for the procedure - do you abort the procedure and eat the costs incurred? Many centers then designated the fingerstick as the "test of record" and it doesn't matter what the Hgb/ Hct value were. Many centers chose to "turn off" the full CBC (what you don't know can't hurt you) and just look at the values you need. The Plt count. This same scenario is true for the WBC count. Some centers have lower/ upper limits of acceptable. Some centers don't want to know... I agree with you that it is helpful information as we all know, it's probably a more accurate number to gauge the donor by ... but since we're not collecting RBCs from the donor, there is little harm that we can do. (Even if we are unable to return the RBCs in the equipment due to access issues, the extracorporeal RBC volume of the most commonly used devices is under 100 mLs of RBCs. Still not enough to "do harm".) One other thing to note... VERY FEW blood centers in the US currently have the ability to even get a day-of-donation CBC/ Platelet count... we're going with the best we have with the information we have.