Logiq 100 pro

All participants underwent thyroid ultrasonography by qualified observers, who had specially trained and passed examination in the project center, using a portable instrument (LOGIQ 100PRO; GE, Milwaukee, WI with a 7.5 MHz linear array transducer). Thyroid volume was calculated as the sum of both lobes volumes estimated according to the formula: V (ml) = 0.479 × width (cm) × depth (cm) × length (cm), without isthmus. Two trained quality control personnel beyond the sonographers were responsible for supervising the accuracy and reliability of the ultrasound results.

Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglycerides (TGs) and low-density lipoprotein cholesterol (LDL-C) were measured with an automatic biochemical analyzer (Mindray BS-180 Analyzer). Bio-Rad reagents were used for HbA1c measurement. We used the hexokinase enzymatic method to measure fasting blood glucose. Serum thyroid-stimulating hormone (TSH) and free thyroxine (FT4) values were measured with an electrochemiluminescence immunoassay on a Cobas 601 analyzer (Roche Diagnostics, Switzerland). Serum TSH, thyroid peroxidase antibodies (TPOAbs) and thyroglobulin antibodies (TGAbs) were measured with an electrochemiluminescence immunoassay on a Cobas 601 analyzer (Roche Diagnostics, Switzerland). When the TSH level exceeded the upper limit of the reference range (0.27-4.20 mIU/L), FT4 and free triiodothyronine (FT3) levels were measured. UIC was measured by inductively coupled plasma−mass spectrometry (Agilent 7700x; Agilent Technologies, Santa Clara, CA). All participants underwent thyroid ultrasonography by specially trained technicians using a portable instrument (LOGIQ 100 PRO; GE, Milwaukee, WI, with 7.5-MHz linear transducers). Two trained quality control personnel apart from the sonographers were responsible for supervising the accuracy and reliability of the ultrasound results.

After the survey was completed, all specimens collected were airlifted through a cold chain system to the institute of Endocrinology of China Medical University for centralized tests. Blood glucose (BG) was tested by the Hexokinase method (Au400 automatic analyzer, Olympus, Japan). Serum triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were determined by Mindray's kit and biochemical detector (BS-180, Mindray, Shenzhen, China). The glycated hemoglobin (HbA1c) assay was measured by Bio Rad reagents. Serum TSH, TPOAb, and TgAb levels were determined by the electrochemical luminescence immunoassay using the Cobas 601 analyzer (Roche Diagnostic, Switzerland). Urine iodine concentration (UIC) was examined using an inductively coupled plasma mass spectrometry (ICP-MS) (Agilent 7700x, Agilent Technologies, USA).
All participants underwent thyroid ultrasonography by qualified medical staffs using a portable instrument (LOGIQ 100 PRO, GE, Milwaukee, WI, USA with 7.5 MHz linear transducers).