What is it used for?The RDW blood test is often part of a complete blood count (CBC), a test that measures many different components of your blood, including red cells. The RDW test is commonly used to diagnose anemia, a condition in which your red blood cells can't carry enough oxygen to the rest of your body. The RDW test may also be used to diagnose:Other blood disorders such as thalassemia, an inherited disease that can cause severe anemiaMedical conditions such as heart disease, diabetes, liver disease, and cancer, especially colorectal cancer.
