References
- Iervasi G, Clerico A. Harmonization of free thyroid hormone tests: a mission impossible? Clin Chem Lab Med. 2011;49(1):43–48.
- Clerico A, Ripoli A, Zucchelli GC, et al. Harmonization protocols for thyroid stimulating hormone (TSH) immunoassays: different approaches based on the consensus mean value. Clin Chem Lab Med. 2015;53(3):377–382.
- Clerico A, Ripoli A, Fortunato A, et al. Harmonization protocols for TSH immunoassays: a multicenter study in Italy. Clin Chem Lab Med. 2017;55(11):1722–1733.
- Hollowell JG, Staehling NW, Flanders WD, et al. Serum TSH, T(4), and thyroid antibodies in the United States population (1988–1994): National Health and Nutrition Examination Survey (NHANES III). J Clin Endocrinol Metab. 2002;87(2):489–499.
- Surks MI, Hollowell JG. Age-specific distribution of serum thyrotropin and antithyroid antibodies in the US population: implications for the prevalence of subclinical hypothyroidism. J Clin Endocrinol Metab. 2007;92(12):4575–4582.
- Boucai L, Surks MI. Reference limits of serum TSH and free T4 are significantly influenced by race and age in an urban outpatient medical practice. Clin Endocrinol. 2009;70(5):788–793.
- Ehrenkranz J, Bach PR, Snow GL, et al. Circadian and circannual rhythms in thyroid hormones: Determining the TSH and free T4 reference intervals based upon time of day, age, and sex. Thyroid. 2015;25(8):954–961.
- Jensen E, Blaabjerg O, Petersen PH, et al. Sampling time is important but may be overlooked in establishment and use of thyroid-stimulating hormone reference intervals. Clin Chem. 2007;53(2):355–356.
- Brabant G, Prank K, Ranft U, et al. Physiological regulation of circadian and pulsatile thyrotropin secretion in normal man and woman. J Clin Endocrinol Metab. 1990;70(2):403–409.
- Mahadevan S, Sadacharan D, Kannan S, et al. Does time of sampling or food intake alter thyroid function test? Indian J Endocrinol Metab. 2017;21(3):369–372.
- Scobbo RR, VonDohlen TW, Hassan M, et al. Serum TSH variability in normal individuals: The influence of time of sample collection. W V Med J. 2004;100(4):138–142.
- Clerico A, Trenti T, Aloe R, et al. A multicenter study for the evaluation of the reference interval for TSH in Italy (ELAS TSH Italian study). Clin Chem Lab Med. 2018;57(2):259–267.
- Wang D, Cheng X, Yu S, et al. Data mining: seasonal and temperature fluctuations in thyroid-stimulating hormone. Clin Biochem. 2018;60:59–63.
- Mirjanic-Azaric B, Stojakovic-Jelisavac T, Vukovic B, et al. The impact of time of sample collection on the measurement of thyroid stimulating hormone values in the serum. Clin Biochem. 2015;48(18):1347–1349.
- Sviridonova MA, Fadeyev VV, Sych YP, et al. Clinical significance of TSH circadian variability in patients with hypothyroidism. Endocr Res. 2013;38(1):24–31.
- Andersen IB, Brasen CL, Christensen H, et al. Standardised resting time prior to blood sampling and diurnal variation associated with risk of patient misclassification: results from selected biochemical components. PLOS One. 2015;10(10):e0140475.
- Weeke J. Circadian variation of the serum thyrotropin level in normal subjects. Scand J Clin Lab Invest. 1973;31(3):337–342.
- Weeke J, Gundersen HJ. Circadian and 30 minutes variations in serum TSH and thyroid hormones in normal subjects. Acta Endocrinol. 1978;89(3):659–672.
- Russell W, Harrison RF, Smith N, et al. Free triiodothyronine has a distinct circadian rhythm that is delayed but parallels thyrotropin levels. J Clin Endocrinol Metab. 2008;93(6):2300–2306.