The difference between fingerstick and venous hemoglobin and hematocrit varies by sex and iron stores.

Background: Fingerstick blood samples are used to estimate donor venous hemoglobin (Hb).

Study Design And Methods: Fingerstick Hb or hematocrit (Hct) was determined routinely for 2425 selected donors at six blood centers, along with venous Hb. Using sex and measures of iron status including absent iron stores (AIS; ferritin < 12 ng/mL), linear regression models were developed to predict venous Hb from fingerstick.