Results of a comparative study of immunoassays for thyroid hormone testing

Abstract

Background: More than 300 public and private laboratories nationwide conduct immunological testing. Immunoassays are mainly based on chemiluminescence enzyme immunoassay (CLEIA) and enzyme-linked fluorescence (ELFA). Hormone testing is the most sensitive markers of the immunological test parameters, and the results depend on the immunoassay method. The main goal of this study was to compare thyroid hormone levels with different immunoassays and comparing the results. Aim: To compare the results of immunoassays for thyroid hormones Materials and Methods: From June 2021 to October 2021, 12 men aged 20-29 working in a Mongolian-Japan hospital without a clinical history of thyroid disease were included in the study and blood samples were collected 3 times. Peripheral blood thyroid hormones TSH, FT3 and FT4 were administered by CLEIA and ELFA according to the manufacturer's instructions. Results: The mean age of the participants was 24.1±2.2. There were no statistically significant differences between the results of the TSH values analyzed by the CLEIA compared with the results of the ELFA (p=0.25). In terms of numbers, it was moderately consistent and representative. (Cohen kappa 0.65, correlation coefÏcient between parameters 0.00). No statistically significant difference was observed when comparing the results of the FT3 parameter analyzed by the CLEIA with the results of the ELFA (p=0.17). In terms of numbers, however, they were weakly consistent and representative. (Cohen kappa 0.24, correlation coefÏcient between parameters 0.06). No statistically significant difference was observed when comparing the results of the FT4 parameter analyzed by the CLEIA with the results of the ELFA (p=0.25). In terms of numbers, it was moderately consistent and representative. (Cohen kappa 0.42, correlation coefÏcient between parameters 0.001). Conclusion: 1. The results of thyroid hormones analyzed by chemiluminescence and enzyme-linked fluorescence were compatible. 2. The results of thyroid hormones determined by chemiluminescence and enzyme-linked fluorescence were representative of each other, but differ in cost.