(1) Among many other elements, the guideline mandates include assay validation and revalidation with demonstration that "positive ER or PgR categories are 90% concordant and negative ER or PgR categories are 95% concordant" (in comparison with clinically validated assays), (1,25) as well as ongoing proficiency testing, at least twice a year, with satisfactory performance defined as "90% correct responses on graded challenges." (1) Proficiency testing data allow analysis of assay variables from large numbers of participant laboratories; in fact, the UK Neqas
program first drew attention to problematic (false positive) staining with the PgR rabbit monoclonal SP2.
(7.) UK NEQAS
. External Quality Assessment Program - Steroid Hormones - Clinical Chemistry.
) distributed 29 external quality specimens with platelet counts less than 64 x [10.sup.9]/L to more than 1100 users of 23 different hematology analyzers.
Problems relating to the laboratory diagnosis of factor XIII deficiency: a UK NEQAS
Similarly, the 2011 UK NEQAS
(United Kingdom National External Quality Assessment Scheme) demonstrated a range of eight titres (2).
Data from distributions of pools of serum distributed by UK NEQAS
over the years 2001-2008 were examined.
The UK National External Quality Assessment Schemes (UK NEQAS
) and other publications have shown that the antigen excess effect can occur at levels of IgG4 around the 95th centile of a normal population, causing missed IgG4 elevations due to prozoning .
External quality assurance of HER2 FISH testing: results of a UK NEQAS
Comparability of antimicrobial susceptibility test results from 22 European countries and Israel: an external quality assurance exercise of the European Antimicrobial Resistance Surveillance System (EARSS) in collaboration with the United Kingdom National External Quality Assurance Scheme (UK NEQAS
Blinded test samples were provided by the United Kingdom National External Quality Assessment Schemes for Leucocyte Immunopheno-typing (UK NEQAS
LI, Sheffield, United Kingdom).