HCT is only for calculation purposes and to ensure our product exceeds FDA standards.
We use the Hematocrit (HCT) number and run that through an algorithm with the Blood Glucose (BG) so we can get a tighter accuracy on the Blood Glucose. By using the additional calculation we can achieve an industry leading accuracy standard of deviation of only 5mg/dl under 100mg/ dl or 5%. The FDA standard is that you can be out by 20% and still be approved, this is what you find with many other meters.
However there is a trade-off here, we have found that the HCT fluctuates and moves around a lot depending on many factors which causes confusion for some users. In hindsight when our engineers said they could put it on the display I should have said no. The meter's primary focus and its FDA clearance for accuracy are for Ketones and Glucose, the H & H is for calculation purposes and should not be used as a diagnostic tool. In the next generation meter, we will bury those numbers.
Here is a link to some more detailed information on what HCT and Hb mean: https://www.emedicinehealth.com/hematocrit_blood_test/page2_em.htm
The test for hematocrit (HCT) as part of the system, is intended for use in the in-vitro quantification of packed red blood cell volume fraction in capillary whole blood as an aid in monitoring the status of total volume of red blood cells. The test reading of haematocrit (HCT) is used only to determine whether the blood test sample is within the acceptable range of β-ketone & blood glucose monitoring system. It should not be used for the diagnosis of anaemia or erythrocytosis.