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Standardisation and Harmonisation. Gifford Batstone National Pathology Programme. April TRUD Release. Revised list of units of measurement PBCL and NLMC New entries – 294 Inclusion of sample type Corrections to names eg BNP Deletions – 299 Duplications Linked to corrections.
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Standardisation and Harmonisation Gifford Batstone National Pathology Programme
April TRUD Release • Revised list of units of measurement • PBCL and NLMC • New entries – 294 • Inclusion of sample type • Corrections to names eg BNP • Deletions – 299 • Duplications • Linked to corrections
Supplementary File • Guidance at present/mandatory in future • Linking analytes (with analysed specimen type) to a single unit of measurement • Addition of Data Combination Indicators • 0 = test not used to trend • 1 = OK to assume combination • 2 = requires a factor • 3 = don’t even think about it • 4 = not yet agreed
Why? - PQAR ‘The continued development of the NLMC to ensure consistency of data and information across the NHS in England should remain a priority. The professional bodies, the IVD manufacturers and others should work towards minimising the differences between analytical processes, requesting and reporting.’ Recommendation 4.66 Pathology Quality Assurance Review
Why? - PQAR ‘Laboratory processes should be harmonised so that patients can be confident about the consistency of their test results, especially as they start to gain access to their personal health records that may contain reports from different pathology services’ Press Release, Pathology Quality Assurance Review
Ref Range Variation • Self reported reference intervals for TSH and fT4. • Each bar represents a different laboratory • Each colour represents a single analytical method • Statistical analysis 750,000 TSH reports gives 0.5 - 5.5 mU/L but ?variation - age, method • Data Finlay MacKenzie UKNEQAS 09/2012
TSH values: Geometric Mean before (A) and after (B) mathematical recalibration 16 immunoassays from 9 different manufacturers analysing the same sample in triplicate. Report of the IFCC Working Group for Standardization of Thyroid Function Tests; Part 1: Thyroid-Stimulating Hormone Thienpont L et al; Clinical Chemistry 56:6 902–911 (2010)
20 - 30 30 - 40 40 - 50 50 - 60 60 - 70 70 - 80 80 - 90 Age group Serum Albumin Variation – Age and Sex Gary Weaving et al male albumin (g/L) female
20 - 30 20 - 30 30 - 40 30 - 40 40 - 50 40 - 50 50 - 60 50 - 60 60 - 70 60 - 70 70 - 80 70 - 80 80 - 90 80 - 90 Average Albumin by laboratory male female age group age group
Reference Ranges 1.17- 9.22 1.59 - 7.27 1.48 - 7.63 1.27 - 9.33 1.59 - 6.89 Comparison of 5 PTH methodsMean values of NEQAS distributions ofSynthetic PTH - Sanjay Khanna
Taking PTH results from 1735 CKD 5 patients in Brighton; Data transformed from Roche to other analytical methods and UKRA ULN applied >9xULN (HTBD) 2-9xULN (optimal) <2xULN (LTBD)
Standardization Harmonization Traceability Categories from ISO 17511 Miller 2012
Standardisation of Reports The emphasis is on the reports More than one approach: • Standardisation of analytical techniques • Use of WHO and similar reference materials • Mathematical alignment of methods • Mean values of different methods • Where no international reference materials • To WHO reference based methods
20 - 30 20 - 30 30 - 40 30 - 40 40 - 50 40 - 50 50 - 60 50 - 60 60 - 70 60 - 70 70 - 80 70 - 80 80 - 90 80 - 90 Same labs Adj Calcium Females average total calcium average adjusted calcium age group age group
female female 80 - 90 80 - 90 80 - 90 80 - 90 70 - 80 70 - 80 70 - 80 70 - 80 60 - 70 60 - 70 60 - 70 60 - 70 male male 50 - 60 50 - 60 50 - 60 50 - 60 40 - 50 40 - 50 40 - 50 40 - 50 30 - 40 30 - 40 30 - 40 30 - 40 20 - 30 20 - 30 20 - 30 20 - 30 Effect of adj to age related alb calcium adjusted by lab calcium re-adjusted for age differences in albumin mean +/- 2sd mean +/- 2sd calcium (mmol/L) calcium (mmol/L)
Comparison of range of results produced with laboratory reference range age 20 – 30 yr Females reference range width
Adjusted Calcium Spread of results vs mean of results F, age 20 -30 spread acceptable? > 10 % % results lower than reference range 1 – 10 % 0.1 – 10 % 0 – 0.1 % mean <1 % < 40 % 1 – 10 % 20 - 40 % 10 – 20 % % results lower than reference range