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Updated: Jun 26, 2026

Generation of a Mouse Spontaneous Autoimmune Thyroiditis Model
Published on: March 17, 2023
Method specific second-trimester reference intervals for thyroid-stimulating hormone and free thyroxine
Rechelle Silvio1, Karly J Swapp, Sonia L La'ulu
1Department of Clinical Laboratory Sciences, Weber State University, Ogden, UT, USA.
Objective:
To determine second trimester reference intervals for TSH and FT4.
Design:
Samples from 3102 subjects were tested for TPO and Tg antibodies.
Methods:
Elecsys E170 reference intervals for TSH and FT4 were determined using antibody-negative samples.
Results:
Second trimester reference intervals for TSH and FT4 were 0.18-4.07 mIU/L and 9.5-15.8 pmol/L, respectively. The Elecsys E170 TSH results were positively biased compared to ARCHITECT i2000(SR) results for these same samples.
Conclusions:
Method-specific reference intervals are required for TSH and FT4.
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