1. All you wanted to know about laboratory tests, but were afraid to ask By Dietmar Stöckl STT Consulting - 7 - The informed patient meeting the laboratory director Standardization & Traceability The problem

2. All you wanted to know about laboratory tests -7- 2 Reminder We heard laboratory testing would be a good idea, but...

3. All you wanted to know about laboratory tests -7- 3 The “Buts” You are healthy in one Lab – but sick in another

4. All you wanted to know about laboratory tests -7- 4 25 hydroxyvitamin D “Vitamin D assays yield markedly differing results; whether an individual is found to have low or normal vitamin D status is a function of the laboratory used. If the medical community is to make progress in correcting widespread hypovitaminosis D, vitamin D measurement must be standardized” Binkley N, et al. Assay variation confounds the diagnosis of hypovitaminosis D: A call for standardization. J Clin Endocrinol Metab 2004;89:3152–7. J Clin Endocrinol Metab

5. All you wanted to know about laboratory tests -7- 5 Parathyroid hormone “It appears unethical that all the companies making different PTH assays could not meet and decide how to standardize and calibrate a consistent circulating PTH measurement. Many physicians are making huge efforts to keep their patients within the target values recommended by the NKF/K-DOQI; however, most of them are misinformed by their PTH measurement”. Torres PU. The need for reliable serum parathyroid hormone measurements. Kidney Int 2006;70:240-3. Kidney Int

6. All you wanted to know about laboratory tests -7- 6 Testosterone Widely used assay methods to measure serum testosterone suffer from a lack of accuracy and sensitivity, making it difficult for physicians to appropriately diagnose and treat androgen-related disorders in women, children, and men. The February 2007 issue of the Journal of Clinical Endocrinology & Metabolism calls for standardizing the methods by which these assays are validated. http://www.endo-society.org/media/press/2007/ EndocrinePositionStatementCallsStandardizedTestosteroneAssays.cfm http://www.cdc.gov/nceh/dls/hormone_standardization.htm J Clin Endocrinol Metab

7. All you wanted to know about laboratory tests -7- 7 Standardization Tip of the iceberg! 25 hydroxyvitamin D Parathyroid hormone Testosterone General problem Steroid hormones Thyroid hormones Protein hormones Glyoprotein hormones Cardiac markers Tumor markers New markers (Cytokines, Growth factors) >And so much more Nearly did'nt dare to come out again! No Titanic around?

8. All you wanted to know about laboratory tests -7- 8 Reference intervals Serum sodium reference interval "Variation in reference intervals was not related to analytical platforms". "The major reason for variation was simply historical, with no scientific foundation". >Not restricted to the UK! http://www.pathologyharmony.co.uk/graphics/Pathology%20Harmony%20N ewsletter%20July%202008.pdf Serum magnesium reference interval Dewitte K. In search of the reference interval of serum magnesium – The last case of Hercule Poirot [in Dutch]. BVLT Tijdschrift 2000;27:169-73. >Origin of the Tietz reference interval could not been traced.

9. All you wanted to know about laboratory tests -7- 9 I type...... what science is that!? It was'nt me who said it.

10. All you wanted to know about laboratory tests -7- 10 The next visit Standardization & Traceability The solution That makes me curious!