"The ' measures the volume of s compared to the total (red blood cells and ). The normal hematocrit for men is 40 to 54%; for women it is 36 to 48%. This value can be determined directly by microhematocrit centrifugation or calculated indirectly. s calculate the hematocrit by multiplying the the red cell number (in millions/mm3) by (MCV, in s). When so assayed, it is subject to the vagaries inherent in obtaining an accurate measurement of the MCV (see Chapter 152)."