Table 2.

Different RBC indices and mathematical formulas used to differentiate between β-TT and IDA.

Hematological index	Formula
Mentzer index (MI) (1973)	MCV/RBC
RDWI (1987)	MCV × RDW/RBC
Shine and Lal (S and L) (1977)	MCV × MCV × MCH/100
Srivastava (1973)	MCH/RBC
Green and King (G and K) (1989)	MCV × MCV × RDW/Hb × 100
Sirdah (2007)	MCV − RBC − (3 × Hb)
Ehsani (2005)	MCV − (10 × RBC)
England and Fraser (E and F) (1973)	MCV − (5 × Hb) − RBC − 3.4
Ricerca (1987)	RDW/RBC
MDHL (1999)	(MCH/MCV) × RBC
MCHD (1999)	MCH/MCV

MDHL index: mean density of Hb/liter of blood; MCHD index: mean cell Hb density.