Routine erythrocyte measurements in diagnosis of iron-deficiency anemia and thalassemia minor.

A study was made of the routine electronic measurements of erythrocyte size and hemoglobin concentration in blood samples from 122 patients with decreased transferrin saturation and 66 patients with elevated levels of hemoglobin A2 or F. The medical histories of these patients were reviewed to identify 52 cases of uncomplicated iron-deficiency anemia and 39 cases of uncomplicated thalassemia minor. Four decision functions were compared for separating these two disorders. The functions evaluated were: D.F'. = MCV--[5 X Hb]-RBC; ratio MCV/RBC; ratio MCH/RBC, and RBC. The rules performed better in the uncomplicated cases than in the routine laboratory defined cases. Only minor differences in the performances of the various decision functions were observed. None was sufficiently accurate for final diagnosis, but they should have value in screening patients and in determining which additional test should be considered.