Objective To compare and analyze the diagnostic efficacy of ultrasound elasticity index and ATA ultra-sound risk system on thyroid nodules.Methods A retrospective analysis was conducted on the clinical data of 118 pa-tients with thyroid nodules confirmed by surgical and pathological examinations.All patients underwent ultrasound elastici-ty index,ATA ultrasound risk system evaluation.The surgical and pathological results were used as the"gold standard"to analyze the diagnostic efficacy of ultrasound elasticity index combined with ATA ultrasound risk system on thyroid nod-ules.Results According to surgical and pathological examination,of 118 patients(146 nodules in total),there were 98 benign nodules,accounting for 67.12%,and 48 malignant nodules,accounting for 32.88%.Using surgical and pathological results as the"gold standard",the ultrasound elastic index diagnosis showed that 16 were misdiagnosed,10 were missed,and Kappa value was 0.54,the ATA ultrasound risk system showed that 8 were misdiagnosed and 4 were missed,with a Kappa value of 0.83,the combined diagnosis of ultrasound elasticity index and ATA ultrasound risk system showed that 4 were misdiagnoses and 2 were missed,with a Kappa value of 0.94.The sensitivity and accuracy of the combination of the two methods in diagnosing benign and malignant thyroid nodules were higher than those of using ultrasound elastic index alone(χ2=6.61,5.42,P<0.05).Conclusion Both the ultrasound elasticity index and ATA ultrasound risk sys-tem have certain diagnostic efficacy for thyroid nodules,but the combination of the two can compensate for the shortcom-ings of a single diagnosis.The diagnostic efficacy is high and can provide an effective basis for determining the nature of thyroid nodules.