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Cited by 176Hormonal and reproductive studiesClinical Laboratory Practices and Quality ControlAdrenal Hormones and Disorders

The DOI matches its Crossref record; 39 of the 39 references it cites were found in a registry or an index.

Predictive accuracy and sources of variability in calculated free testosterone estimates

Sartorius, Gideon, Ly, Lam P, Sikaris, Ken, McLachlan, Robert, Handelsman, David J·2009·Annals of Clinical Biochemistry: International Journal of Laboratory Medicine
DOI 10.1258/acb.2008.008171
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Abstract

Background: Serum free testosterone (FT) concentrations are commonly requested, but because reference FT methods are too laborious various calculational algorithms for FT based on total testosterone (TT) and sex hormone-binding globulin (SHBG) are frequently used. This study provides the first large-scale evaluation of the predictive accuracy and sources of variability for different FT formulae compared with direct laboratory measurements. Methods: Using a large data-set of direct FT measurements by centrifugal ultrafiltration, the predictive accuracy of five different formulas for cFT (four existing plus a new formula) is evaluated in 3975 consecutive blood samples. In a second data-set of 124 samples from a reference panel of healthy eugonadal young men, we estimate the relative influence of the five algorithms and eight different TT and two SHBG assays including all available commercial total TT and SHBG assays together with a gas chromatography/mass spectrometry T reference method. Results: cFT formulae show wide discrepancies with equilibrium-binding algorithms showing systematic overestimation relative to direct FT measurements, whereas two empirical cFT methods were more concordant. Variations between commercially available TT immunoassays have a strong impact on calculation of FT with TT assays contributing 82.2% of overall variance compared with 13.7% for the cFT algorithms and 4.1% for the SHBG assays. Conclusions: If FT measurements are requested and direct measurement impractical, cFT formulae using TT and SHBG immunoassays provide an approximation to direct FT measurement that is strongly dependent on the TT, cFT formula used and, to a lesser extent, SHBG immunoassays.

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Crossref · 10.1258/acb.2008.008171

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Research works printed but not linked: 2

  1. Kratzsch J, 2001, Clin Lab, 47, 73
  2. Burke CW, 1972, J Endocrinol, 53, xxvi

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Metadata

Authors
Sartorius, G., Ly, L. P., Sikaris, K., McLachlan, R., & Handelsman, D. J.
Affiliations
  • The University of Sydney (AU)
  • The University of Melbourne (AU)
  • Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia
Corresponding author
Handelsman, David J
ORCID
Venue
Annals of Clinical Biochemistry: International Journal of Laboratory Medicine
Publisher
SAGE Publications
Published
2009-01-22
Volume
46
Issue
2
Pages
137-143
ISSN
  • 0004-5632 (ISSN-L)
  • 1758-1001
DOI
10.1258/acb.2008.008171
OpenAlex
W2042309501
Cited by
175
References
39
Citations by year
2025: 8 · 2024: 5 · 2023: 3 · 2022: 6 · 2021: 12 · 2020: 5 · 2019: 8 · 2018: 16 · 2017: 16 · 2016: 10 · 2015: 16 · 2014: 12 · 2013: 9 · 2012: 16
FWCI
11.61
Type
journal article
Language
en
Open access
closed
Licence
journals.sagepub.com/page/policies/text-and-data-mining-license (tdm)
Locations
  • Annals of Clinical Biochemistry International Journal of Laboratory Medicine (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Research Foundation
  • Johnson and Johnson
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Hormonal and reproductive studies
  • Health Sciences › Health Professions › Medical Laboratory Technology › Clinical Laboratory Practices and Quality Control
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Adrenal Hormones and Disorders
Keywords
free testosterone, total testosterone, sex hormone-binding globulin, prediction accuracy, assay variability, centrifugal ultrafiltration, eugonadal men
MeSH terms
Humans, Male, Middle Aged, Testosterone

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