Chorionic Villus - CVS|
Accredited UKAS 7872
Chorionic Villus testing.
PURPOSE OF PROGRAMME:
to establish the cytogenetic analytical and interpretative capabilities of the participating laboratory specific to CVS.
|g-banded images of chorionic villi plus other preliminary prenatal test results as applicable||G-banding|
MATERIAL PROVIDED: Online images of G-banded metaphases plus other tests as applicable
DISTRIBUTIONS PER YEAR: 1
SAMPLES PER DISTRIBUTION: 2
FREQUENCY OF DISTRIBUTION: 1 distribution in accordance with the annual EQA timetable.
PROGRAMME OF ANALYSIS:
G-banded images and other tests (e.g. FISH) are presented for analysis together with a referral card and additional clinical information to mimic a routine diagnostic case. Instructions and a user guide are available on the website. Images can be downloaded from the website and imported into your image analysis system. The participant analyses the images, interprets the results and reports via the CEQAS website. The EQA is open for 5 weeks. Results can be entered at any time during this period.
All EQA cases are validated prior to release. Results are assessed by a panel of experts against set marking criteria based upon professional guidelines. There are three marking categories, Analytical, Interpretation and Clerical Accuracy. Each category carries two points. Deductions are made in accordance with the severity of the omission. A “critical error” is an error made in either the analytical or interpretive category that could lead to serious clinical consequences or imply a significa
Satisfactory/Poor. A non-submission is also given a poor performance.
PERSISTENT POOR PERFORMANCE:
This is defined as: a) Two poor performances in any constitutional cytogenetic EQA in which the laboratory participates, over three or more distributions of material, within a 36 month rolling period; b) A poor performance within one year following a previous persistent poor performance designation.
The External Quality Assessment Scheme for Molecular Genetics was founded in 1991. In 1999 the Service became known as the UK National External Quality Assessment Service for Molecular Genetics. UK NEQAS for Molecular Genetics is part of NHS Lothian.