Radiochromic dye dosimeter solutions as reference measurement systems

Author(s):  
Mahnaz Farahani ◽  
William L. McLaughlin
Author(s):  
Mauro Panteghini ◽  
Ferruccio Ceriotti

AbstractAn issue associated with standardization efforts is the need to develop useful reference intervals (RI). Lack of proper RI may hamper the implementation of standardization in Laboratory Medicine as standardization can modify analyte results and, without adequate RI, this can impair the result interpretation. Once defined, RI obtained with analytical procedures that produce results traceable to the corresponding reference system can be transferred among laboratories, providing that they use commercial assays that produce results traceable to the same reference system and populations have the same characteristics. Multicenter studies are needed for a robust definition of traceable RI, using experimental protocols that include well defined prerequisites. Particularly, employed methods must produce results that are traceable to the reference system for that specific analyte. Thus, the trueness of laboratories producing reference values should be verified and, if necessary, experimental results corrected in accordance with correlation results with the selected reference. If requirements in the adoption of traceable RI are fulfilled, the possibility of providing RI that are applicable to any laboratory, able to produce results traceable to the reference system, is realistic. The definition of traceable RI should hopefully cause the disappearance of different RI employed for the same analyte, providing more effective information to clinicians.


2002 ◽  
Vol 323 (1-2) ◽  
pp. 73-87 ◽  
Author(s):  
Linda M. Thienpont ◽  
Katleen Van Uytfanghe ◽  
André P. De Leenheer

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6301
Author(s):  
Daniela Istrate ◽  
Abderrahim Khamlichi ◽  
Soureche Soccalingame ◽  
Jorge Rovira ◽  
Dominique Fortune ◽  
...  

Current standard EN 50463-2 indicates the tests and the requirements to be satisfied for an energy measurement system of a traction unit for railway applications. Some of these tests are to be done with several harmonics superposed on the rated voltage, respectively current. However, no calibration systems satisfying the standard requirements were available few years ago. The work performed in the EURAMET project “MyRailS” leads to the development of fictive power sources and reference measurement systems described in this paper. Therefore, it is possible to generate distorted 25 kV-50 Hz voltages with harmonics up to 5 kHz and 90° phase-fired currents up to 500 A with harmonics up to 5 kHz. The generated power is measured by developed traceable reference systems with accuracy better than 0.5%.


2020 ◽  
Vol 58 (8) ◽  
pp. 1250-1256 ◽  
Author(s):  
Elena Aloisio ◽  
Erika Frusciante ◽  
Sara Pasqualetti ◽  
Ilenia Infusino ◽  
Magdalena Krintus ◽  
...  

AbstractBackgroundLaboratory professionals should independently verify the correct implementation of metrological traceability of commercial measuring systems and determine if their performance is fit for purpose. We evaluated the trueness, uncertainty of measurements, and transferability of six clinically important enzyme measurements (alanine aminotransferase [ALT], alkaline phosphatase [ALP], aspartate aminotransferase [AST], creatine kinase [CK], γ-glutamyltransferase [γGT], and lactate dehydrogenase [LDH]) performed on the Abbott Alinity c analytical system.MethodsTarget values and associated uncertainties were assigned to three pools for each enzyme by using the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) reference measurement procedures (RMPs) and the pools were then measured on the Alinity system. Bias estimation and regression studies were performed, and the uncertainty associated with Alinity measurements was also estimated, using analytical performance specifications (APS) derived from biological variability of measurands as goals. Finally, to validate the transferability of the obtained results, a comparison study between two Alinity systems located in Milan, Italy, and Bydgoszcz, Poland, was carried out.ResultsCorrect implementation of traceability to the IFCC RMPs and acceptable measurement uncertainty fulfilling desirable (ALP, AST, LDH) or optimal APS (ALT, CK, γGT) was verified for all evaluated enzymes. An optimal alignment between the two Alinity systems located in Milan and Bydgoszcz was also found for all enzyme measurements.ConclusionsWe confirmed that measurements of ALT, ALP, AST, CK, γGT, and LDH performed on the Alinity c analytical system are correctly standardized to the IFCC reference measurement systems and the system alignment is consistent between different platforms.


Author(s):  
Hanane Saadeddine ◽  
Mohamed Agazar ◽  
Dominique Fortune

Driven by the need for traceable measurement methods, LNE has developed and characterized new reference measurement systems for the calibration of HV impulses, including lightning impulses (1, 2 µs/ 50 µs) and switching impulses (250 µs/ 2500 µs), according to new requirements of IEC 60060-1 and IEC 60060-2. This paper describes new reference measurement systems, which have been developed and fully characterized at LNE. In addition, the paper describes the test procedure for accurate measurements especially for in-situ calibrations in 5 successive steps; measurements of radiofrequency disturbances, step response of voltage dividers, measurement of the scale factors of voltage dividers, calibration of digitizer’s channels and ranges, measurement of the voltage linearity of the divider under calibration up to maximum voltage.


2005 ◽  
Vol 51 (1) ◽  
pp. 161-168 ◽  
Author(s):  
Linda M Thienpont ◽  
Katleen Van Uytfanghe ◽  
John Marriot ◽  
Peter Stokes ◽  
Lothar Siekmann ◽  
...  

Abstract Background: Assuring/demonstrating metrologic traceability of in vitro diagnostics necessitates the availability of measurand-specific reference measurement systems (RMSs) and the possibility for industry to work with competent reference measurement laboratories (RMLs). Here we report the results of a European project to investigate the feasibility of developing a RMS for serum total thyroxine. Methods: Four candidate RMLs (cRMLs) developed/implemented variants of a candidate reference measurement procedure (cRMP) based on isotope dilution–liquid chromatography–mass spectrometry. The sole constraint implemented was calibration with a common thyroxine primary calibrator. The RMPs were externally validated and assessed for comparability in round-robin trials using common samples, i.e., 5 lyophilized and 33 frozen native sera. At the same time, the performance of the cRMLs organized in a network was assessed. For uniform external quality assessment, common performance specifications were agreed on. Results: All cRMLs performed the cRMPs with fulfillment of the predefined specifications: total and between-laboratory CVs ≤2.0% and 2.5%, respectively, and a systematic deviation ≤0.9%, estimated with a target assigned from the mean of means obtained by the cRMLs. The mean expanded uncertainty for value assignment to the native sera was 2.1%. Conclusions: A network of cRMLs, with externally conformed competence to properly perform RMPs, has been established. Performance specifications were defined and will form the basis for admittance of new network members. A serum panel, successfully targeted during the validation process, is available for split-sample measurements with commercial routine measurement procedures. The model can now be used for other measurands for which traceability to the Système International d’Unités is needed.


Sign in / Sign up

Export Citation Format

Share Document