Comparison of Thyroid -Stimulating Hormone and Free Thyroxine Immunoassays Performed on Immulite 2000 and Maglumi 800 Automated Analyzers

  • Sonja Kuzmanovska Faculty of Medicine, Institute of Pathophysiology and Nuclear Medicine, Ss. Cyril and Methodius University of Skopje, Skopje, Republic of Macedonia
  • Daniela Miladinova Faculty of Medicine, Institute of Pathophysiology and Nuclear Medicine, Ss. Cyril and Methodius University of Skopje, Skopje, Republic of Macedonia
Keywords: Immunoassay, Thyroid-stimulating hormone, FT4, Within-run imprecision, Comparison of methods


OBJECTIVE: Our goal was to evaluate the analytical performance of the novel immunoassay platform and to compare the agreement between thyroid-stimulating hormone (TSH) and FT4 results, obtained by novel and currently used platform.

MATERIALS AND METHODS: Both immunoassay platforms, current Immulite 2000 and novel Maglumi 800, are based on chemiluminecsence immunoassay method. Analytical performance was evaluated by the use of serum pools and commercial quality control samples. The comparison study was carried out with 80 serum samples. Obtained results were analyzed by descriptive statistics, Mann–Whitney U-test, and Paired t-test. Method comparison was performed with Passing-Bablok regression analysis and Bland-Altman plots.

RESULTS: TSH Maglumi 800 showed better within-run precision for both concentration ranges (1.7–2.8 CV%) in comparison to Immulite 2000 (4.4–5.7 CV%). FT4 Maglumi 800 imprecision was higher compared with Immulite 2000 FT4 in both within-run (3.5–3.9 CV% vs. 4.9–6.6 CV%) and between-run (3.6–4.2 CV% vs. 4.6–5.9 CV%) tests. Mann–Whitney U-test for TSH revealed non-significant difference between data (p = 0.9011). Regression analysis showed no systematic (intercept = 0.01), nor proportional (slope = 0.9781) differences. Non-significant bias was observed in Bland-Altman Plots. For FT4, we found significant differences between methods using paired t-test (t39 = 10.5, p < 0.0001) and significant difference (p = 0.00745) with Mann–Whitney U-test. Bland-Altman plot revealed 22.8% average bias.

CONCLUSION: TSH evaluation showed good precision and close agreement between Maglumi 800 and Immulite 2000 methods, which assures transferability of results. However, FT4 performance evaluation revealed higher imprecision of Maglumi 800 platform and significant differences of test results.


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Ross DS, Burch HB, Cooper DS, Greenlee MC, Laurberg P, Luiza Maia A, et al. 2016 American thyroid association guidelines for diagnosis and management of hyperthyroidism and other causes of thyrotoxicosis. Thyroid. 2016;26(10):1343-421. PMid:27521067

Spencer CA, Lo Presti JS, Patel A, Guttler RB, Eigen A, Shen D, et al. Applications of a new chemiluminometric thyrotropin assay to subnormal measurement. J Clin Endocrinol Metab. 1990;70(2):453-60. PMid:2105333

Garber JR, Cobin RH, Gharib H, Hennessey JV, Klein I, Mechanick JI, et al. Clinical practice guidelines for hypothyroidism in adults: Cosponsored by the American association of clinical endocrinologists and the American thyroid association. Thyroid. 2012;22(12):1200-35. PMid:23246686

Vaidya B, Ukoumunne OC, Shuttleworth J, Bromley A, Lewis A, Hyde C, et al. Variability in thyroid function test requests across general practices in south-west England. Qual Prim Care. 2013;21(3):143-8. PMid:23968263

Daucourt V, Saillour-Glenisson F, Michel P, Jutand MA, Abouelfath A. A multicenter cluster randomized controlled trial of strategies to improve thyroid function testing. Med Care. 2003;41(3):432-41. PMid:12618646

Willis EA, Datta BN. Effect of an educational intervention on requesting behaviour by a medical admission unit. Ann Clin Biochem. 2013;50(Pt2):166-8. PMid:23345588

Hendriks HA, Kotlandt W, Verweij WM. Analytical performance comparison of five new generation immunoassay analyzers. Ned Tijdschr Klin Chem 2000;25:170-7.

Steele BW, Wang E, Klee GG, Thienpont LM, Soldin SJ, Sokoll LJ, et al. Analytic bias of thyroid function tests: Analysis of a college of American pathologists fresh frozen serum pool by 3900 clinical laboratories. Arch Pathol Lab Med. 2005;129(3):310-7. PMid:15737023

Rawlins ML, Roberts WL. Performance characteristics of six third-generation assays for thyroid-stimulating hormone. Clin Chem. 2004;50(12):2338-44. PMid:15472032

Clinical and Laboratory Standards Institute. Measurement Procedure Comparison and Bias Estimation Using Patient Samples; Approved Guideline. 3rd ed. CLSI Document EP09-A3. Wayne, PA: Clinical and Laboratory Standards Institute; 2013.

Bilić-Zulle L. Comparison of methods: Passing and Bablok regression. Biochem Med (Zagreb) 2011;21(1):49-52. PMid:22141206

Giavarina D. Understanding bland altman analysis. Biochem Med (Zagreb). 2015;25(2):141-51. PMid:26110027

LeFevre ML, U.S. Preventive Services Task Force. Screening for thyroid dysfunction: U.S. preventive services task force recommendation statement. Ann Intern Med. 2015;162(9):641-50. PMid:25798805

Biondi B, Bartalena L, Cooper DS, Hegedus L, Laurberg P, Kahaly GJ. The 2015 european thyroid association guidelines on diagnosis and treatment of endogenous subclinical hyperthyroidism. Eur Thyroid J. 2015;4(3):149-63. PMid:26558232

Schneider C, Feller M, Bauer DC, Collet TH, Costa BR, Auer R, et al. Initial evaluation of thyroid dysfunction are simultaneous TSH and fT4 tests necessary? PLoS One. 2018;13(4):1-12. PMid:29709030

Minchinela J, Ricós C, Perich C, Fernández-Calle P, Alvarez V, Doménech MV, et al. Desirable Specifications for Total Error, Imprecision, and Bias, Derived from Intra and Inter-individual Biologic Variation; 2014. Available from: http://www.westgard. com/biodatabase-2014-update.htm. [Last accessed on 2019 Sep].

NCCLS. Evaluation of Precision Performance of Quantitative Measurement Methods; Approved Guideline. 2nd ed. NCCLS Document EP5-A2. Wayne, Pennsylvania; NCCLS; 2004.

Andersen S, Bruun NH, Pedersen KM, Laurberg P. Biologic variation is important for interpretation of thyroid function tests. Thyroid. 2003;13(11):1069-78. PMid:14651790

Tetteh TA, Wijeratne S, Swaminathan R. Intraindividual variation in serum thyroid hormones, parathyroid hormone and insulin-like growth factor 1. Ann Clin Biochem. 2008;45(Pt 2):167-9. PMid:18325180

Zhang S, Wang W, Zhao H et al. Status of internal quality control for thyroid hormones immunoassays from 2011 to 2016 in China. J Clin Lab Anal. 2018;32(1):1-10. PMid:28205257

Thienpont LM, Van Uytfanghe K, Beastall G, Faix JD, Ieiri T, Miller WG, et al. Report of the IFCC working group for standardization of thyroid function tests part 2: Free thyroxine and free triiodothyronine. Clin Chem. 2010;56(6):912-20. PMid:20395624

Thienpont LM, Van Uytfanghe K, Van Houcke S, Das B, Faix JD, MacKenzie F, et al. A progress report of the IFCC committee for standardization of thyroid function tests. Eur Thyroid J. 2014;3(2):109-16. PMid:25114874

Stockl D, Van Uytfanghe K, Van Aelst S, Thienpont LM. A statistical basis for harmonization of thyroid stimulating hormone immunoassays using a robust factor analysis model. Clin Chem Lab Med. 2014;52:965-72. PMid:24566365

Faix JD, Miller WG. Progress in standardizing and harmonizing thyroid function tests. Am J Clin Nutr. 2016;104(Suppl):913S-7S. PMid:27534642

Thienpont LM, Faix JD, Beastall G. Standardiztion of free T4 and harmonization of TSH measurements: A request for input from endocrinologists and other physicians. Eur Thyroid J. 2015;4(4):271-2. PMid:26835432

Barth JH, Luvai A, Jassam N, Mbagaya W, Kilpatrick ES, Narayanan D, et al. Comparison of method-related reference intervals for thyroid hormones: Studies from a prospective reference population and a literature review. Ann Clin Biochem. 2018;55(1)107-12. PMid:28081637

How to Cite
Kuzmanovska S, Miladinova D. Comparison of Thyroid -Stimulating Hormone and Free Thyroxine Immunoassays Performed on Immulite 2000 and Maglumi 800 Automated Analyzers. Open Access Maced J Med Sci [Internet]. 2020Apr.25 [cited 2020Oct.23];8(B):168-74. Available from: