The importance of measuring the uncertainty of Second Generation Total Testosterone Analysis

Abstract

The importance of measuring the uncertainty of second-generation total testosterone analysis Objectives: Testosterone is present in both genders; however, the level is low in women, whereas it is high in men. A measurement of total testosterone (TT) is widely requested by clinicians in daily practice, and is used in both diagnosis and treatment. The aim of this study was to calculate the measurement uncertainty of TT and to make a contribution of new research to the literature. Methods: The identification of measurement, factors that can affect the measured value, laboratory reproducibility bias (uRw 2 ), laboratory and method bias measurement uncertainty (Ubias), uncertainty of calibration (uCref ), uncertainty of external quality control data (uEQA), combined measurement uncertainty (Uc), and extended measurement uncertainty (U) were evaluated and reported. Results: The results of determining the measurement uncertainty of TT measurement in this laboratory were as follows: 1) uRw 2 = (RSDlevel 1 2 + RSDlevel 2 2 + RSDlevel 3 2 ) / n: (20.90 2 + 17.48 2 + 7.00 2 ) / 3 = 263.79; 2) uCref = 0.012; Cref = 2.35; k=2. RuCref = (100 x uCref ) / (k x Cref ): (100 x 0.012) / (2 x 2.35) = 0.255; RuCref 2 = 0.065; 3) Ubias 2 = RuCref 2 + uEQA 2 : 0.065 + 105.60 = 105.67; 4) Uc=√ (uRw 2 + ubias 2 ): √ (263.79 + 105.67) = 19.22; 5) U = 2√ (uRw 2 + ubias 2 ): 2 x 19.22 = 38.44%; 6) Result report (serum TT): ± 38.44%. Conclusion:The measurement uncertainty result for TT calculated using the top-down method was ± 38.44% with a 95% confidence interval. The individual measurement uncertainty result for each test should be given to the clinician and the patient together with the test results. The TT measurement uncertainty of other methods should also be known at the international level.

Measurement uncertainty in biochemical parameters

“…The data obtained from external quality control, internal quality control and method validation studies are at the center of approaches to be used in the calculation of the measurement uncertainty for biochemical/chemical methods [4]. The methods adopted in order to determine measurement uncertainty, the ISO and the Guide to the Expression of Uncertainty of Measurement (GUM) guidelines, are continuously being investigated, in order to provide the most effective guidelines [13]. Because these calculations are complicated and elaborate, their practical applicability is declining [13,14].…”

“…The methods adopted in order to determine measurement uncertainty, the ISO and the Guide to the Expression of Uncertainty of Measurement (GUM) guidelines, are continuously being investigated, in order to provide the most effective guidelines [13]. Because these calculations are complicated and elaborate, their practical applicability is declining [13,14]. In 2012, ''Quantifying Uncertainty in Analytical Measurement'' titled, the Eurachem/CITAC Guide CG 4 was published [15].…”

Interpol review of toxicology 2016–2019

“…The measurement uncertainty of total testosterone analysis using chemiluminescent microparticle immunoassay technology was calculated by Ayyildiz [ 30 ]. Two top-down approaches including the single laboratory validation approach and the proficiency testing approach were used to estimate measurement uncertainty of whole blood tacrolimus mass concentration obtained by LC-MS/MS [ 31 ].…”

Experimental Investigation of the Interference Effect of Drugs Used in Intensive Care for Sedation on Biochemical Markers

“…Ulagay, İstanbul, Türkiye), propofol (propofol, %1, 200 mg/20 mL, ampul; Fresenius Kabi, İstanbul, Türkiye), midazolam (zolamid, 5 mg/5 mL, ampul; VEM, Ankara, Türkiye), deksmedetomidin (precedex, 200 µg/2 mL, flakon; Meditera, İzmir, Türkiye) ilaçları kullanıldı. (6)(7)(8)(9)(10) . Etkilenen laboratuvar parametrelerinin fizyolojik bir durumdan mı yoksa ölçüm hatasından mı kaynaklandığını tespit etmenin zorluğundan dolayı interferans çalışmalarının invitro ortamda kontrol solüsyonlarıyla karşılaştırılarak yapılması tercih edilir.…”