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Quality Assurance Unit - Scheme Details

Clinical Chemistry
PT Number
Scheme title
Tissue Lead
Suitable testing methods
Atomic Absorption Spectroscopy or ICP-MS
Reporting format
umol per kg dry weight.
Statistical analysis is used to convert the participants results to a Z score which can then be used to identify questionable or outlier results by a robust statistical procedure (any results outside of +/-3 SDs of the mean is discounted). The z-score analysis is based on calculation of mean and standard deviation values.
Authorised reports are published electronically. These show intended results and results from all participants contain a link to Histograms.
Results to be returned within
21 days
Number of samples in each distribution
Sample Type
Approx 2g of freeze dried powdered liver tissue samples
Packaging and transport details
Non-infectious substance. UK - Normal post. Overseas - courier. Courier delivery will incur additional costs. Please contact the QA unit for details
Number of distributions per year
Various aspects of the Proficiency testing schemes may at times be subcontracted. When this occurs it is placed with a competent subcontractor and the Quality Assurance Unit is responsible to the scheme participants for the subcontractors work.
Accreditation status
ISO/IEC 17043: 2010 Conformity assessment – General requirements for proficiency testing.
Date scheme started
Pre 2007
Fresh liver has a dry matter of approximately 20%. Use 1/5 of the weight of wet tissue normally used i.e. instead of 1g wet tissue use 0.2g dry powder. Please dry the powder using your routine laboratory procedure and then use 0.2g freshly dried powder for the assay. Remember to allow for this in the final calculation. i.e. Results x 5.
For price and detail of distribution months please see price list or contact:
Back to PT Schemes Prices & Timetable | Print scheme details | Version 8. January 2018