The red cell distribution width (RDW) blood test measures how equal your red blood cells are in size. One of several tests included in a complete blood count ... blood test is high, it means ...

The calculation doctors use for this is (RDW-SD)/(MCV)×100 ... The outlook for someone with a high RDW count varies considerably depending on the cause of this test result.

High RDW values may mean you have a nutrient deficiency, anemia, or other underlying condition. This test is commonly performed as a part of a complete blood count (CBC). The CBC determines the ...