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Search Publications by: Johanna Camara (Fed)

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Displaying 1 - 25 of 87

Certification of Standard Reference Material(R) 965c Glucose in Frozen Human Serum

March 13, 2025
Author(s)
Amanda Bayless, William Davis, Elena Wood, Abraham Kuri Cruz, Johanna Camara, Blaza Toman, Komal Dahya, Katherine Earl, Chui Tse, Uliana Danilenko, Hubert Vesper
Standard Reference Material (SRM) 965c Glucose in Frozen Human Serum is intended for use in validating methods for the determination of glucose in human serum and plasma. A unit of SRM 965c consists of three ampoules each of four materials: Level 1, Level

Commutability Assessment of New Standard Reference Materials (SRMs) for Determining Serum Total 25-Hydroxyvitamin D using Ligand Binding and Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS) Assays

January 10, 2025
Author(s)
Stephen Wise, Etienne Cavalier, Pierre LUKAS, Stephanie Peeters, caroline Le Goff, Laura Briggs, Emma Williams, Ekaterina Mineva, Christine Pfeiffer, Hubert Vesper, Christian Popp, Christian Beckert, Jan Schultess, Kevin Wang, Carole Tourneur, Camille Pease, Dominik Osterritter, Ralf Fischer, Ben Saida, Chao Dou, Satoshi Kojima, Hope Weiler, Agnieszka Bielecki, Heather Pham, Alexandra Bennett, Shawn You, Amit Ghoshal, Chistian Vogl, James Freeman, Neil Parker, Samantha Pagliaro, Jennifer Cheek, Jie Li, Hisao Tsukamoto, Karen Galvin, Kevin Cashman, Hsuan-Chieh Liao, Andrew Norbert Hoofnagle, Jeffery Budd, Adam Kuszak, Ashley Boggs-Russell, Carolyn Burdette, Grace Hahm, Federica Nalin, Johanna Camara
Commutability is where the measurement response for a reference material (RM) is the same as for an individual patient sample with the same concentration of analyte measured using two or more measurement systems. Assessment of commutability is essential

Recommendations for assessing commutability of a replacement batch of a secondary calibrator certified reference material

December 16, 2024
Author(s)
Liesbet Deprez, Jesper Johansen, Thomas Keller, Jeffrey Budd, Neil Greenberg, Cas Weykamp, Sverre Sandberg, MAURO PANTEGHINI, Ferruccio Ceriotti, Elizabeth Barczak, Robert Rej, Pernille Kjeilen Fauskanger, Finlay MacKenzie, Johanna Camara, Alicia Lyle, W. Greg Miller, VINCENT DELATOUR
Commutable secondary certified reference materials (CRMs) play an essential role in the calibration hierarchy of many in-vitro diagnostic measurement procedures used in the medical laboratory. Therefore, sustainable availability of these CRMs is crucial to

Feasibility of Metrological Traceability Implementation Using the Joint Committee on Traceability in Laboratory Medicine Database Entries Including the Fulfillment of "Fit-for-Purpose" Maximum Allowable Measurement Uncertainty

September 24, 2024
Author(s)
MAURO PANTEGHINI, Johanna Camara, VINCENT DELATOUR, Katleen Van Uytfanghe, Hubert Vesper, Tianjiao Zhang
Background: In previous publications, the Task Force on Reference Measurement System Implementation proposed a procedural approach combining a critical review of entries available in the Joint Committee on Traceability in Laboratory Medicine (JCTLM)

Bilirubin measurements in neonates: uniform neonatal treatment can only be achieved by improved standardization

July 26, 2024
Author(s)
Christian Hulzebos, Johanna Camara, Miranda van Berkel, VINCENT DELATOUR, Stanley Lo, Agnes Mailloux, Marcel Schmidt, Mercy Thomas, Lindsey Mackay, Ronda Greaves
Measurement of total serum bilirubin (TSB) concentration is the gold standard approach for diagnosing neonatal unconjugated hyperbilirubinemia. It is of utmost importance that the measured TSB concentration is sufficiently accurate to prevent

Recommendations for setting a criterion and assessing commutability of sample materials used in external quality assessment/proficiency testing schemes

November 2, 2023
Author(s)
Sverre Sandberg, Pernille Fauskanger, Jesper Johansen, Thomas Keller, Jeffrey Budd, Neil Greenberg, robert rej, MAURO PANTEGHINI, VINCENT DELATOUR, Ferruccio Ceriotti, Liesbet Deprez, Johanna Camara, Finlay MacKenzie, Alicia Lyle, Eline van der Hagen, Chris Burns, W. Greg Miller
It is important for external quality assessment materials (EQAMs) to be commutable with clinical samples; i.e., they should behave like clinical samples when measured using end-user clinical laboratory in vitro diagnostic medical devices (IVD-MDs). Using

Recommendations for Setting a Criterion for Assessing Commutability of Secondary Calibrator Certified Reference Materials

August 11, 2023
Author(s)
W. Greg Miller, Thomas Keller, Jeffrey Budd, Jesper Johansen, Mauro Panteghini, Neil Greenberg, Vincent Delatour, Ferruccio Ceriotti, Robert Rej, Johanna Camara, Liesbet Deprez, Finlay MacKenzie, Alicia Lyle, Eline van der Hagen, Chris Burns, Pernille Fauskanger, Sverre Sandberg
A secondary higher-order calibrator is required to be commutable with clinical samples to be suitable for use in the calibration hierarchy of an end-user clinical laboratory in vitro diagnostic medical device (IVD-MD). Commutability is a property of a

Determination of 24,25-dihydroxyvitamin D3 in Vitamin D External Quality Assessment Scheme samples using a reference measurement procedure

May 9, 2023
Author(s)
Stephen Wise, Grace Hahm, Carolyn Burdette, Susan Tai, Johanna Camara, Adam Kuszak, Emma Williams
Ninety archived human serum samples from the Vitamin D External Quality Assessment Scheme (DEQAS) were analyzed using a reference measurement procedure (RMP) based on isotope dilution liquid chromatography - tandem mass spectrometry (ID LC-MS/MS) for the

Development of an Improved Standard Reference Material for Folate Vitamers in Human Serum

December 12, 2022
Author(s)
Johanna Camara, Jeanita Pritchett, Yasmine Daniels, Mary Bedner, Michael Nelson, Mark Lowenthal, Zia Fazili, Christine Pfeiffer, Karen W. Phinney, Katherine E. Sharpless, Lane C. Sander, Katrice Lippa, James H. Yen, Adam Kuszak, Stephen Wise
The US National Institute of Standards and Technology (NIST) developed a Standard Reference Material® (SRM®) 3949 Folate Vitamers in Frozen Human Serum to replace SRM 1955 Homocysteine and Folate in Human Serum. The presence of increased endogenous levels

Assessment of Serum Total 25-Hydroxyvitamin D Assays for Vitamin D External Quality Assessment Scheme (DEQAS) Materials Distributed at Ambient and Frozen Conditions

November 9, 2021
Author(s)
Johanna Camara, Christopher T. Sempos, Emma L. Williams, Graham D. Carter, Julia C. Jones, Carolyn Burdette, Grace Hahm, Federica Nalin, David L. Duewer, Adam J. Kuszak, J. M. Betz, Andrew Hoofnagle, Pierre Lukas, E. Cavalier, Ramon Durazo-Arvizu, P. M. Crump, Christian Popp, Christian Beckert, Glen Van Slooten, Patrick Gradon, Joelle Morgand, Sarah Paul, Bruno Emanuelli, Angelo Maggio, Fiona Ivison, Ralf Fischer, Jody M. van den Ouweland, Chung S. Ho, Emmett W. Law, Jean-Nicolas Simard, Renaud Gonthier, Brett Holmquist, Manisha S. Patwardhan, Marcelo C. Batista, Heather Pham, Sarah Meadows, Eugene Jansen, Dilshad A. Khan, Kimberly Robyak, Mark Kilbane, Neil Parker, Vincent Chen, Robert Fitzgerald, Sohail Mushtaq, Michael W. Clarke, Norma Breen, Christine Simpson, Stephen A. Wise
The Vitamin D External Quality Assessment Scheme (DEQAS) distributes human serum samples four times per year to over 1000 participants worldwide for the determination of total serum 25-hydroxyvitamin D [25(OH)D)]. These samples are stored at −40 °C prior

Optimizing Available Tools for Obtaining Result Standardization: A Joint Committee on Traceability in Laboratory Medicine (JCTLM) Project

October 12, 2021
Author(s)
Mauro Panteghini, Federica Braga, Johanna Camara, Vincent Delatour, Katleen Van Uytfanghe, Hubert Vesper, Tianjiao Zhang
BACKGROUND: The JCTLM created a Task Force on Reference Measurement System Implementation (TFRMSI) to provide guidance on metrological traceability implementation for the in vitro diagnostics (IVD) community. CONTENT: TF-RMSI investigated the reference

Metrological Tools for the Reference Materials and Reference Instruments of the NIST Material Measurement Laboratory

September 16, 2021
Author(s)
Carlos R. Beauchamp, Johanna Camara, Jennifer Carney, Steven J. Choquette, Kenneth D. Cole, Paul C. DeRose, David L. Duewer, Michael Epstein, Margaret Kline, Katrice Lippa, Enrico Lucon, John L. Molloy, Michael Nelson, Karen W. Phinney, Maria Polakoski, Antonio Possolo, Lane C. Sander, John E. Schiel, Katherine E. Sharpless, Michael R. Winchester, Donald Windover
The National Institute of Standards and Technology (NIST), formerly the National Bureau of Standards, was established by the U.S. Congress in 1901 and charged with establishing a measurement foundation to facilitate U.S. and international commerce. NIST

Certification of Standard Reference Materials(R) 2969 and 2970: Vitamin D Metabolites in Frozen Human Serum (Total 25-Hydroxyvitamin D Low Level) and (25-Hydroxyvitamin D2 High Level)

September 2, 2021
Author(s)
Grace Hahm, Michael Nelson, Johanna Camara, Blaza Toman
Standard Reference Materials (SRMs) 2969 and 2970 are intended for 1) use in validating methods for determining concentrations of 25-hydroxyvitamin D2 (25(OH)D2) and 25-hydroxyvitamin D3 (25(OH)D3) in human serum and plasma and 2) value assigning in house