England & Fraser Index (Thalassemia vs Iron Deficiency)
England & Fraser discriminant function: MCV − RBC − (5 × Hb) − 3.4; a negative value favors beta-thalassemia trait over iron-deficiency anemia.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- MCV
- 65 fL
- RBC count
- 5.5 ×10¹²/L
- Hemoglobin
- 12.5 g/dL
Result: England & Fraser discriminant function -6.4 — favors beta-thalassemia trait (cutoff 0).
The tool opens with these values already filled in. Replace them with your own.
What the result means
- < 0
- Favors beta-thalassemia trait.
- > 0
- Favors iron-deficiency anemia. DF = MCV - RBC - (5 x Hb) - 3.4. A screen, not a diagnosis — confirm with electrophoresis and iron studies.
What you enter
- MCV
- RBC count
- Hemoglobin
How this is calculated
England JM, Fraser PM. Differentiation of iron deficiency from thalassaemia trait by routine blood-count. Lancet. 1973;1(7801):449-452. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.