How does hematocrit show the proportion of blood made up of red blood cells?

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blood analysis The physical and chemical properties of a sample of blood are examined during blood analysis. The examination of blood is important for the accurate diagnosis of disease.

The hematocrit is a diagnostic procedure used to determine the proportion of blood volume occupied by red blood cells.

During the analysis, a blood sample is placed in a calibrated tube and centrifuged. This process forces the blood components to separate into three distinct layers based on density:
* Bottom layer: Packed red blood cells (erythrocytes).
* Middle layer: A reddish-gray band of white blood cells and platelets.
* Top layer: Plasma.

The hematocrit value is specifically calculated as the percentage of the total blood volume represented by the bottom layer of packed red blood cells. This measurement is a vital diagnostic tool, as an abnormally thick layer may indicate polycythemia, while an abnormally thin layer can be a sign of iron-deficiency anemia.1