Abstract:   Objective　To evaluate the application significance of glucose-6-phosphate dehydrogenase（G6PD）activity detection in screening of thalassemia. Methods　A total of 229 blood samples of pregnant women were detected by polymerase chain reaction（PCR）and reverse dot-blotting as golden standard. They were classified into 2 groups according to genetic testing results: thalassemia group（163 cases）and control group（66 cases）. The G6PD activities were detected，and the results were compared with those of PCR. The sensitivity，specificity，positive predictive value（PPV），negative predictive value（NPV），positive likelihood ratio（+LR）and negative likelihood ratio（-LR）were analyzed. The results of G6PD activity detection in screening of thalassemia were analyzed and evaluated by receiver operating characteristic（ROC）curve. Results　G6PD activity in thalassemia group was（13.16±3.23）U/gHb，which was higher than that in control group[（10.63±2.18）U/gHb]（t＝5.83，P＝0.000）. The area under the ROC curve was 0.757. The optimal cut-off value was 11.95U/gHb. The sensitivity，specificity，PPV，NPV，+LR and -LR were 0.693，0.773，0.88，0.50，3.05 and 2.52，respectively. Conclusions　G6PD activity detection has some screening significance in the diagnosis of thalassemia. The increasing of G6PD activity should be highly suspected as thalassemia to further confirm by gene detection.

Key words: Glucose-6-phosphate dehydrogenase, Thalassemia, Receiver operating characteristic curve, Screening