Iron Deficiency Anemia (IDA) and Beta Thalassemia Minor (BTM) are the most common
causes of microcytic hypochromic anemia. In the last four decades many formulas have been proposed
to discriminate between two common causes of microcytic hypochromic anemia. An ideal
discrimination index should have a high sensitivity and specificity and should be easy to calculate. The
distinction between IDA and BTM is important in many respects. In our study, the performance of
twelve indices were tested to distinguish IDA from BTM, two common causes of microcytic anemia.
Materials and methods: There were two groups which were evaluated as IDA and BTM, we examined
the diagnostic accuracy of five red cell parameters [red blood cell (RBC), mean corpuscular volume
(MCV), hemoglobin (Hb) ,mean corpuscular hemoglobin (MCH), red blood cell distribution width (RDW)]
and we calculated twelve indices [Menzier Index (MI), Green and King (GK), Red Blood Cell Distribution
Width Index (RDWI), England & Fraser (EF), RBC, Sirdah Index (SI), Ricarca Index (R), Srivastava (S),
Shine & Lal (SL), Ehsani (E), Red Cell Distribution Width (RDW), 11T].
Results: Among the twelve discrimination indices, 11T index was the most efficient in differentiating
IDA from BTM. 11T index had the highest Youdens index (69,8%) and accuracy (81,2%).
Conclusion: 11T index was the most effective in discriminating IDA from BTM. RBC, GK, SI and RDWI
could be used as a screening tool rather than discrimination indices.