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Academic and nonacademic laboratories perform equally on CIQC immunohistochemistry proficiency testing.

https://arctichealth.org/en/permalink/ahliterature113089
Source
Am J Clin Pathol. 2013 Jul;140(1):55-60
Publication Type
Article
Date
Jul-2013
Author
Zhongchuan Will Chen
Heather Neufeld
Maria A Copete
John Garratt
C Blake Gilks
Emina E Torlakovic
Author Affiliation
Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada.
Source
Am J Clin Pathol. 2013 Jul;140(1):55-60
Date
Jul-2013
Language
English
Publication Type
Article
Keywords
Academic Medical Centers
Breast Neoplasms - diagnosis
Canada
Data Collection
Female
Hospitals, Rural
Hospitals, Urban
Humans
Immunohistochemistry - standards
Laboratories - standards
Laboratory Proficiency Testing - standards
Paraffin Embedding
Pathology - standards
Quality Assurance, Health Care
Reproducibility of Results
Tissue Array Analysis
Tumor Markers, Biological - analysis
Workload
Abstract
To test whether academic centers (ACs) are more successful than nonacademic centers (NACs) in immunohistochemistry (IHC) external quality assessment challenges in the Canadian Immunohistochemistry Quality Control (CIQC) program.
Results of 9 CIQC challenges for breast cancer marker (BM) and various non-breast cancer marker (NBM) tests were examined. Success rates were compared between AC/NAC laboratories and those located in small or large cities. Performance was also correlated with annual IHC case volumes.
There was no statistically significant difference in performance in any of the comparisons. However, overall performance on BM was significantly better (P
PubMed ID
23765534 View in PubMed
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Proficiency of drug susceptibility testing of Mycobacterium tuberculosis against pyrazinamide: the Swedish experience.

https://arctichealth.org/en/permalink/ahliterature106709
Source
Int J Tuberc Lung Dis. 2013 Nov;17(11):1486-90
Publication Type
Article
Date
Nov-2013
Author
S. Hoffner
K. Angeby
E. Sturegård
B. Jönsson
A. Johansson
M. Sellin
J. Werngren
Author Affiliation
Department of Preparedness, Swedish Institute for Communicable Disease Control, Solna, Sweden.
Source
Int J Tuberc Lung Dis. 2013 Nov;17(11):1486-90
Date
Nov-2013
Language
English
Publication Type
Article
Keywords
Amidohydrolases - genetics
Antitubercular Agents - therapeutic use
Drug Resistance, Bacterial
Humans
Laboratory Proficiency Testing - standards
Microbial Sensitivity Tests - standards
Mycobacterium tuberculosis - drug effects - genetics - growth & development
Observer Variation
Predictive value of tests
Pyrazinamide - therapeutic use
Quality Control
Quality Indicators, Health Care - standards
Reproducibility of Results
Sequence Analysis, DNA
Sweden
Tuberculosis - diagnosis - drug therapy - microbiology
Abstract
Pyrazinamide (PZA) is a key drug in the treatment of tuberculosis (TB), including multidrug-resistant TB. Drug susceptibility testing (DST) of Mycobacterium tuberculosis against PZA is not included in the World Health Organization's yearly proficiency testing. There is an increasing need to establish quality control of PZA DST.
To evaluate the performance of PZA DST and to introduce a quality assurance system for the test in Sweden.
Panels with PZA-susceptible and -resistant isolates were used in three rounds of proficiency testing in all five Swedish clinical TB laboratories and our reference laboratory. All laboratories used the MGIT 960 system. Minimum inhibitory concentrations (MICs) were determined and the pncA gene was sequenced to further characterise the 52 panel strains.
Good agreement was seen between the phenotypic PZA DST and pncA sequence data, and MIC determination confirmed high levels of resistance. However, in contrast to other drugs, for which correct proficiency test results were observed, specificity problems occurred for PZA DST in some laboratories.
In Sweden, using panel testing, differences were seen in the proficiency of TB laboratories in correctly identifying PZA susceptibility. Improved results were noted in the third round; PZA has therefore been included in yearly proficiency testing.
PubMed ID
24125455 View in PubMed
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Therapeutic Drug Monitoring of Lithium: A Study of the Accuracy and Analytical Variation Between Laboratories in Denmark.

https://arctichealth.org/en/permalink/ahliterature272958
Source
Ther Drug Monit. 2015 Aug;37(4):466-71
Publication Type
Article
Date
Aug-2015
Author
Tina Mose
Per Damkier
Magnus Petersen
Steen Antonsen
Source
Ther Drug Monit. 2015 Aug;37(4):466-71
Date
Aug-2015
Language
English
Publication Type
Article
Keywords
Denmark
Drug Monitoring - standards - statistics & numerical data
Humans
Ion-Selective Electrodes
Laboratory Proficiency Testing - standards - statistics & numerical data
Lithium - blood
Reference Values
Spectrophotometry
Abstract
Serum lithium is monitored to ensure levels within the narrow therapeutic window. This study examines the interlaboratory variation and inaccuracy of lithium monitoring in Denmark.
In 16 samples consisting of (1) control materials (n = 4), (2) pooled patient serum (n = 5), and (3) serum from individual patients (n = 7), lithium was measured in 19 laboratories using 20 different instruments. The lithium concentrations were targeted by a reference laboratory. Ion-selective electrode (n = 5), reflective spectrophotometric (RSM, n = 5), and spectrophotometric (n = 10) methods were used.
Acceptable accuracy-interpreted as total differences from target values (bias) less than or equal to ±12%-was generally found in patient samples above 0.7 mmol/L. Below 0.7 mmol/L, 8 instruments had 2 or more patient samples exceeding a difference to the targeted reference value of >12%. Seven of these instruments had a systematic positive or negative bias and more so at lower lithium concentrations. Three poorly calibrated instruments were found in the ion-selective electrode group, 3 in the spectrophotometric group, and 2 in the RSM group. The instruments using reflectance spectrophotometry (RSM) were on average 21% positively biased when measuring control materials. However, this effect was not observed in patient samples.
Large interlaboratory variation was found below 0.7 mmol/L because of 7 instruments with a poor accuracy and 1 with poor precision. Methods should be recalibrated or substituted. Controls below 0.7 mmol/L are recommended.
PubMed ID
26192891 View in PubMed
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