Testosterone Measured by 10 Immunoassays and by Isotope-Dilution Gas Chromatography–Mass Spectrometry in Sera from 116 Men, Women, and Children

BACKGROUND: Commercially available testosterone immunoassays give divergent results, especially at the low concentrations seen in women. We compared immunoassays and a nonimmunochemical method that could quantify low testosterone concentrations. METHODS: We measured serum testosterone in 50 men, 55 ... View More