Reviewed: 13. Juli 2026
RDW Red Cell Distribution Width (RDW)
Unit: %
Quick Explanation
RDW measures how much red blood cells vary in size. An elevated value can indicate early iron, vitamin B12, or folic acid deficiency, especially combined with an abnormal MCV. Discuss an elevated RDW with your doctor.
📊 Reference Values
ℹ️ Reference ranges may vary slightly between laboratories. Always compare your value with the reference range from your own lab report.
🔍 Possible Causes
Value too high — possible causes
- ·Iron deficiency
- ·Vitamin B12 or folic acid deficiency
- ·Mixed anemia
- ·After blood transfusion
This list shows possible causes — not a diagnosis. Only your doctor can correctly interpret your result.
🩺 Questions for Your Doctor
- →What does my elevated RDW mean together with my MCV?
- →Should my iron and vitamin status be checked?
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Medical Disclaimer
The content on this page is for general information only and does not replace professional medical advice, diagnosis, or treatment. Always consult your doctor or pharmacist for health-related questions. Lab values should always be assessed in the context of your personal medical history.