Abstract
OBJECTIVE: To determine the appropriateness of using MCV/MCH as screening test for beta-thalassemia trait in the present population and also to find the most appropriate cutoff for optimum sensitivity of these indices. METHODS: It was an analytical, observational and cross-sectional study. Complete blood count followed by high-performance liquid chromatography (HPLC) was performed. The MCV and MCH levels were noted in cases and controls. RESULTS: Thalassemia trait was found in 66 out of 1300 antenatal women with anemia. The MCV and MCH were significantly low in cases (p = 0.0001). MCV had a better AUC (0.650) than MCH (0.635). The most suitable cutoff value of MCV was calculated as 72 fl (sensitivity-63.7%, specificity-68.3%, PPV-9.7%, LR-2.0) and that for MCH was 24 pg (sensitivity-63.6%, specificity-59.4%, PPV-7.7%, LR-1.5) using Youden's index. When MCH (cutoff of 28 pg) and MCV were combined (cutoff of 74 fl), the sensitivity and specificity were 95% and 16%, respectively. CONCLUSION: The sensitivity and specificity of MCV and MCH alone had low detection rate when used in combination had high sensitivity but the specificity was low; therefore, HPLC should be the preferred screening test for beta-thalassemia in Indian women.