Objective To study the application of ABCD3-I score in predicting the risk of early is-chemic stoke after transient ischemic attack (TIA) .Methods One hundred and eighty-two carotid TIA patients were divided into low risk group (n=40) ,moderate risk group (n=74)and high risk group (n=68) according to their ABCD2 ,ABCD3 and ABCD3-I scores .The incidence of ischemic stroke was observed within 7 days after TIA .Results The area under the ROC curve for ischemic stroke within 7 days after TIA was 0 .625 ,0 .713 and 0 .831 ,respectively .Twenty-seven patients (14 .8% ) developed ischemic stroke within 7 days after TIA .The incidence of ischemic stroke was significantly higher in moderate and high risk groups than in low risk group and in high risk group than in moderate risk group (6 .8% vs 0% ,32 .4% vs 0% ,32 .4% vs 6 .8% ,P< 0 .01) .The ABCD3-I socre was positively related with the incidence of ischemic stroke within 7 days after TIA (r=0 .486 ,P<0 .01) ,suggesting that ABCD3-I socre could significantly affect the incidence of ischemic stroke within 7 days after TIA (P<0 .05) .Conclusion ABCD3-I score can effectively predict the risk of early ischemic stroke after TIA ,and can thus be used in assessment and treat-ment of T IA .