Home Medicine Patient pools and the use of “patient means” are valuable tools in quality control illustrated by a bone-specific alkaline phosphatase assay
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Patient pools and the use of “patient means” are valuable tools in quality control illustrated by a bone-specific alkaline phosphatase assay

  • Maja Hinge , Erik D. Lund , Ivan Brandslund , Torben Plesner and Jonna S. Madsen EMAIL logo
Published/Copyright: August 11, 2015
Clinical Chemistry and Laboratory Medicine (CCLM)
From the journal Clinical Chemistry and Laboratory Medicine (CCLM) Volume 54 Issue 3

Abstract

Background: Quality control (QC) is an essential part of clinical biochemistry to ensure that laboratory test results are reliable and correct. Those tests without a defined reference method constitute a special challenge, as is the case with bone-specific alkaline phosphatase (BAP).

Methods and Results: The present study reports an example where a shift in a BAP assay was detected by use of a patient pool and supported by a retrospective calculation of “patient mean”, while the external QC and specific assay control material were unaffected by the shift.

Conclusions: Patient pools and the use of patient means remain a useful and inexpensive procedure for internal QC.

Keywords: analytical bias; bone-specific alkaline phosphatase; patient means; patient pool; quality control
Corresponding author: Jonna S. Madsen, Department of Clinical Immunology and Biochemistry, Lillebaelt Hospital, Kabbeltoft 25, 7100 Vejle, Denmark; and Institute of Regional Health Research, University of Southern Denmark, Odense, Denmark, Phone: +45 79406501; E-mail:

Acknowledgments

We would like to thank Liselotte Bjerregård Lauersen for her attentiveness in the laboratory work and for recognizing the steady increase in the results of BAP in the PP.

Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

Research funding: None declared.

Employment or leadership: None declared.

Honorarium: None declared.

Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.

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Received: 2015-3-31
Accepted: 2015-7-8
Published Online: 2015-8-11
Published in Print: 2016-3-1

©2016 by De Gruyter

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https://doi.org/10.1515/cclm-2015-0308
Keywords for this article
analytical bias; bone-specific alkaline phosphatase; patient means; patient pool; quality control

Articles in the same Issue

  1. Frontmatter
  2. Editorial
  3. The way of prostate cancer diagnostics
  4. Review
  5. Statistical methods used in the calculation of geriatric reference intervals: a systematic review
  6. Opinion Paper
  7. The side effects of translational omics: overtesting, overdiagnosis, overtreatment
  8. Genetics and Molecular Diagnostics
  9. Rapid detection of non-deletional mutations causing α-thalassemia by multicolor melting curve analysis
  10. General Clinical Chemistry and Laboratory Medicine
  11. Patient pools and the use of “patient means” are valuable tools in quality control illustrated by a bone-specific alkaline phosphatase assay
  12. Long-term stability of glucose: 96-h study using Terumo Glycaemia tubes
  13. Glucose is stable during prolonged storage in un-centrifuged Greiner tubes with liquid citrate buffer, but not in serum and NaF/KOx tubes
  14. Croatian laboratories have a good knowledge of the proper detection and management of hemolyzed, icteric and lipemic samples
  15. Fetal exposure to ethanol: relationship between ethyl glucuronide in maternal hair during pregnancy and ethyl glucuronide in neonatal meconium
  16. Comparing the effect of isotopically labeled or structural analog internal standards on the performance of a LC-MS/MS method to determine ciclosporin A, everolimus, sirolimus and tacrolimus in whole blood
  17. Relationship between matrix metalloproteinase-9 and oxidative stress in drug-free male schizophrenia: a case control study
  18. Comparison of functional fibrinogen (FF/CFF) and FIBTEM in surgical patients – a retrospective study
  19. Reference Values and Biological Variations
  20. Assessment of serum free light chain levels in healthy adults immediately after marathon running
  21. Pharmacokinetics of a novel dosing regimen of oral melatonin in critically ill patients
  22. Cancer Diagnostics
  23. An epidemiology-based model as a tool to monitor the outbreak of inappropriateness in tumor marker requests: a national scale study
  24. Comparative analysis of prostate cancer specific biomarkers PCA3 and ERG in whole urine, urinary sediments and exosomes
  25. Infectious Diseases
  26. Comparative evaluation of the Aptima HIV-1 Quant Dx assay and COBAS TaqMan HIV-1 v2.0 assay using the Roche High Pure System for the quantification of HIV-1 RNA in plasma
  27. Evaluating the use of procalcitonin in an asymptomatic, HIV-infected antiretroviral therapy-naïve, South African cohort
  28. Diabetes
  29. Early prediction of gestational diabetes: a practical model combining clinical and biochemical markers
  30. Letters to the Editors
  31. Highly-trained dogs’ olfactory system for detecting biochemical recurrence following radical prostatectomy
  32. More on the accuracy of the Architect enzymatic assay for hemoglobin A1c and its traceability to the IFCC reference system
  33. Assessing quality from an accuracy-based HbA1c proficiency survey
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