RDW-CV (Red Cell Distribution Width - Coefficient of Variation) is a blood test that measures the variability in the size of red blood cells. This test determines the breadth of the erythrocyte size distribution. The normal accepted RDW-CV range is generally between approximately 11.0% and 15.0%.
RDW-CV is a percentage value calculated by dividing the standard deviation of the Mean Corpuscular Volume (MCV) by the MCV and multiplying by 100. This value indicates the heterogeneity of red blood cell size, meaning how varied the cell sizes are.
A high RDW-CV value indicates that the variability in the average size of red blood cells is greater than normal. This condition can be an indicator of various conditions such as macrocytic anemia, iron deficiency anemia, or vitamin B12 deficiency.