Proposal of a score combining red blood cell indices for early differentiation of beta-thalassemia minor from iron deficiency anemia.

This study evaluates the diagnostic reliability of 11 red blood cells indices, together with our new index, referred to as '11T', in differentiation of beta-thalassemia minor (BTm) from iron deficiency anemia (IDA). A total of 129 patients with microcytic anemia were involved in a retrospective study, 80 with IDA and 49 with BTm. Using an automatic program, we calculated 11 discrimination indices and a new score, 11T, based on the results of these 11 tests. To confirm the interest of 11T, we performed a prospective study with 53 patients. 11T was most effective in differentiating BTm from IDA: 11T had the highest Youden's index (83%) and the best percentage of correctly identified patients (93%) and gave optimal performance in our prospective study. We proposed a score, 11T, which is able to discriminate between IDA and BTm with high specificity and high sensitivity in order to conduct the appropriate confirmatory examination.