Red Blood Cell (RBC) Indices
Reviewed
Red blood cell (RBC) indices measure your red blood cells' size, shape, and quality. They are part of a complete blood count (CBC) and are used to help diagnose different types of anemia. A health care professional will take a blood sample from a vein in your arm. There is very little risk to having a blood test; you may have slight pain or bruising at the needle site, but most symptoms go away quickly.
Preparation and collection
No special preparation is needed.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- Reference ranges and units are not provided in the source; interpretation should be done by your healthcare professional.
- RDW results alone are not diagnostic and must be combined with other indices and tests.
What to do next
Talk to your health care provider if you have questions about your results. Your provider will consider your symptoms, medical history, and the results of other blood tests to understand your results.
Evidence source
U.S. National Library of Medicine: Red Blood Cell (RBC) Indices