1. All you wanted to know about laboratory tests, but were afraid to ask By Dietmar Stöckl STT Consulting - 2 - The informed patient meeting the laboratory director Metrology Measurand 1

2. All you wanted to know about laboratory tests -2- 2 Metrology Without your husband? It will be boaring he said! We should understand the basics, I said! Otherwise, we may be lost from the start. You have a point there.

3. All you wanted to know about laboratory tests -2- 3 VIM – The metrologist’s bible International vocabulary of metrology (VIM) It’s all about measurement Measurand Quantity intended to be measured Quantity format: “System–Component (analyte); Kind of quantity” Serum–creatinine; amount-of- substance concentration, x µmol/L I knew it was thunderstorms!

4. All you wanted to know about laboratory tests -2- 4 Measurand S-creatinine Alkaline picrate active substances! (Jaffe) Creatinine! (Enzymatic) I knew it was thunderstorms!

5. All you wanted to know about laboratory tests -2- 5 Measurand It's CREATININE! Quantity intended to be measured NO! All clinical studies were with Jaffe! It's CREATININE! eGFR: trueness-based just introduced

6. All you wanted to know about laboratory tests -2- 6 Measurand It's CREATININE, I type I knew why I did'nt want to come!

7. All you wanted to know about laboratory tests -2- 7 The next visit Thyroid stimulating hormone (TSH) More about measurands

8. All you wanted to know about laboratory tests -2- 8 Resources ISO/IEC Guide 99:2007. International vocabulary of metrology – Basic and general concepts and associated terms (VIM). International Organization for Standardization: Geneva, 2007 (VIM = Vocabulaire International de Métrologie). JCGM 200:2008. International vocabulary of metrology – Basic and general concepts and associated terms (VIM). International Bureau of Weights and Measures (BIPM); Joint Committee for Guides in Metrology (JCGM): Paris, 2008. Freely available at: http://www.bipm.org/en/publications/guides/vim.html See also, Clinical and Laboratory Standards Institute (CLSI): http://www.clsi.org/Content/NavigationMenu/Resources/HarmonizedTermi nologyDatabase/Harmonized_Terminolo.htm