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Cited by 131Hormonal and reproductive studiesSperm and Testicular FunctionAdrenal Hormones and Disorders

Calculation of Bioavailable and Free Testosterone in Men: A Comparison of 5 Published Algorithms

de Ronde, Willem, van der Schouw, Yvonne T, Pols, Huibert AP, Gooren, Louis JG, Muller, Majon, Grobbee, Diederick E, de Jong, Frank H·2006·Clinical Chemistry
DOI 10.1373/clinchem.2005.063354
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Abstract

Background: Estimation of serum concentrations of free testosterone (FT) and bioavailable testosterone (bioT) by calculation is an inexpensive and uncomplicated method. We compared results obtained with 5 different algorithms. Methods: We used 5 different published algorithms [described by Sodergard et al. (bioTS and FTS), Vermeulen et al. (bioTV and FTV), Emadi-Konjin et al. (bioTE), Morris et al. (bioTM), and Ly et al. (FTL)] to estimate bioT and FT concentrations in samples obtained from 399 independently living men (ages 40–80 years) participating in a cross-sectional, single-center study. Results: Mean bioT was highest for bioTS (10.4 nmol/L) and lowest for bioTE (3.87 nmol/L). Mean FT was highest for FTS (0.41 nmol/L), followed by FTV (0.35 nmol/L), and FTL (0.29 nmol/L). For bioT concentrations, the Pearson correlation coefficient was highest for the association between bioTS and bioTV (r = 0.98) and lowest between bioTM and bioTE (r = 0.66). FTL was significantly associated with both FTS (r = 0.96) and FTV (r = 0.88). The Pearson correlation coefficient for the association between FTL and bioTM almost reached 1.0. Bland-Altman analysis showed large differences between the results of different algorithms. BioTM, bioTE, bioTV, and FTL were all significantly associated with sex hormone binding globulin (SHBG) concentrations. Conclusion: Algorithms to calculate FT and bioT must be revalidated in the local setting, otherwise over- or underestimation of FT and bioT concentrations can occur. Additionally, confounding of the results by SHBG concentrations may be introduced.

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Authors
de Ronde, W., van der Schouw, Y. T., Pols, H. A., Gooren, L. J., Muller, M., Grobbee, D. E., & de Jong, F. H.
Affiliations
  • Department of Endocrinology, Vrije Universiteit Medical Center, Amsterdam, The Netherlands
  • Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, The Netherlands
  • Erasmus MC (NL)
  • Amsterdam UMC Location Vrije Universiteit Amsterdam (NL)
  • University Medical Center Utrecht (NL)
  • Departments of Internal Medicine; and Epidemiology and Biostatistics, Erasmus Medical Center, Rotterdam, The Netherlands
ORCID
Venue
Clinical Chemistry
Publisher
Oxford University Press (OUP)
Published
2006-09-01
Volume
52
Issue
9
Pages
1777-1784
ISSN
  • 0009-9147 (ISSN-L)
  • 1530-8561
DOI
10.1373/clinchem.2005.063354
OpenAlex
W2108328747
Cited by
131
References
44
Citations by year
2026: 3 · 2025: 4 · 2024: 2 · 2023: 4 · 2022: 3 · 2021: 8 · 2020: 5 · 2019: 4 · 2018: 5 · 2017: 12 · 2016: 3 · 2015: 8 · 2014: 9 · 2013: 10 · 2012: 7
FWCI
6.11
Type
journal article
Language
en
Open access
closed
Licence
academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model (vor)
Locations
  • Clinical Chemistry (publishedVersion)
  • PubMed (publishedVersion)
  • Pure Amsterdam UMC (publishedVersion)
  • Amsterdam UMC (VU Amsterdam) - Institutional Repository (publishedVersion)
  • EUR Research Repository (Erasmus University Rotterdam) (publishedVersion)
  • EUR Research Repository (Erasmus University Rotterdam) (submittedVersion)
  • Data Archiving and Networked Services (DANS) (submittedVersion)
Topics
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Hormonal and reproductive studies
  • Health Sciences › Medicine › Reproductive Medicine › Sperm and Testicular Function
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Adrenal Hormones and Disorders
Keywords
free testosterone, bioavailable testosterone, sex hormone-binding globulin, algorithm comparison, men, algorithm validation
MeSH terms
Adult, Aged, Aged, 80 and over, Algorithms, Carrier Proteins, Cross-Sectional Studies, Humans, Male, Middle Aged, Serum Albumin, Sex Hormone-Binding Globulin, Testosterone

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