en Radiation Biology Radiation Biology تحقيق بديع Original Research <div style="text-align: justify;"><span style="font-size:10pt"><span style="text-justify:newspaper"><span style="text-kashida-space:50%"><span style="line-height:119%"><span style="font-family:Calibri"><span style="color:black"><span lang="en-US" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-US">Background:</span></span></span></span></span></span> <span lang="en-GB" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:black"><span style="language:en-GB">Malignant thyroid nodules are defined as malignancies in the thyroid gland, and usually refer to thyroid cancer. We aimed to retrospectively assess the differences in ultrasonic description and Chinese-Thyroid Imaging Reporting and Data System (C-TIRADS) classification in the interpretation of malignant thyroid nodules by observers (with different years of experience). </span></span></span></span><span lang="en-GB" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-GB">Materials and Methods: </span></span></span></span></span></span><span lang="en-GB" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:black"><span style="language:en-GB">A total of 119 patients with thyroid nodules (119 nodules, all with postoperative pathological results) treated from January 2020 to January 2023 were selected and subjected to color Doppler ultrasonography. According to the experience of observers (n=4) in thyroid ultrasonography, the subjects were divided into Group A, B, C and D (years of experience: &le;2 years, 3-5 years, 6-10 years, and >10 years). Then the acquired ultrasound images were assessed and classified. </span></span></span></span><span lang="en-GB" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-GB">Results: </span></span></span></span></span></span><span lang="en-GB" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:black"><span style="language:en-GB">The ultrasound signs of C-TIRADS classification in patients with malignant thyroid nodules, such as degree of enhancement, uniformity of enhancement, mode of enhancement, circular enhancement and mode of washout, were significantly different from those of the subjects with benign thyroid nodules (P<0.05). In Groups A, B, C, and D, the areas under the curves were 0.734, 0.776, 0.823 and 0.885, and the Youden indexes were 0.339, 0.562, 0.630 and 0.835, respectively. The interobserver agreement in the determination of C-TIRADS 4/5/6 of malignant thyroid nodules and the overall agreement were both good (Kappa=0.735, 0.627, 0.651, and 0.765). </span></span></span></span><span lang="en-GB" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:#1f497d"><span style="font-style:italic"><span style="font-weight:bold"><span style="language:en-GB">Conclusion: </span></span></span></span></span></span><span lang="en-GB" style="font-size:9.0pt"><span style="font-family:Calibri"><span style="color:black"><span style="language:en-GB">The overall interobserver agreement in the selection of C-TIRADS ultrasound descriptors is good.</span></span></span></span></span></span></span></span></span></span></div> Classification, Doppler ultrasonography, color, malignancy, observation, thyroid gland. 411 416 http://ijrr.com/browse.php?a_code=A-10-1-1510&slc_lang=en&sid=1 J. Li 7900319475328460033511 7900319475328460033511 No Department of Ultrasound, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu Province, China J. Wang 7900319475328460033512 7900319475328460033512 No Department of Ultrasound, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu Province, China J. Qiao 7900319475328460033513 7900319475328460033513 No Department of Ultrasound, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu Province, China X. Zheng 7900319475328460033514 7900319475328460033514 No Department of Ultrasound, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu Province, China X. Lu 281933813@qq.com 7900319475328460033515 7900319475328460033515 Yes Department of Ultrasound, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, Jiangsu Province, China