A NEW VALID FORMULA IN DIFFERENTIATING IRON DEFICIENCY ANEMIA FROM ß–THALASSEMIA TRAIT

Objective: to compare the validity of a new index (hb×rdw×100/ (rbc)2×mchc) with twelve discriminating functions (dfs) to differentiate iron deficiency anemia (ida) and beta-thalassemia trait(ß –tt). methodology: a total of 823 patients (317 ida and 506 ß –tt) aged 15 to 35- year- old were enrolled in this study. the diagnostic sensitivity, specificity and other validity parameters were calculated to assess the diagnostic reliability of the novel index [keikhaei index (ki)] vis-a-vis the other published dfs [mentzer index (mi), green & king index (g&ki),red cell distribution width index (rdwi), england & fraser index (e&fi), bessman and feinstein index (b&fi), telmissani et al index (ti), srivastava and bevington index (s&bi), shine and lal index (s&li), ricerca et al index (ri), ehsani et al index (ei), sirdah et al index (si), and red blood cell count(rbc)] were calculated in all patients. results: all thirteen dfs didn’t have the sensitivity and specificity of 100%. the ki, rdwi, g&ki and e&fi showed the most sensitivity and specificity for both ida and tt; moreover, the lowest reliable indices belonged to b&fi, s&li and ri. conclusion: according to youden’s index (yi), dfs in the order of highest to lowest were ki > g&ki > rdwi > e&fi > rbc> m i> ei > ti > si > s&bi > ri> s&li >b&fi.