No major month to month variation in free testosterone levels in aging males. Minor impact on the biological diagnosis of ‘andropause’

A Critical Evaluation of Simple Methods for the Estimation of Free Testosterone in Serum

Alex Vermeulen, L. Verdonck, Jean‐Marc Kaufman · The Journal of Clinical Endocrinology & Metabolism · 1999 · 3.7K citations

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Longitudinal Effects of Aging on Serum Total and Free Testosterone Levels in Healthy Men

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Age Trends in the Level of Serum Testosterone and Other Hormones in Middle-Aged Men: Longitudinal Results from the Massachusetts Male Aging Study

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Age, Disease, and Changing Sex Hormone Levels in Middle-Aged Men: Results of the Massachusetts Male Aging Study*

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Longitudinal changes in testosterone, luteinizing hormone, and follicle-stimulating hormone in healthy older men

John E. Morley, Fran E. Kaiser, Horace M. Perry et al. · Metabolism · 1997 · 833 citations

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