Age-specific total testosterone levels in Japanese adolescent boys and girls using electrochemiluminescent immunoassay

Abstract

(Introduction) In sports fields worldwide, total testosterone levels are about to be used to qualify female athletes for competition, and LC-MS/MS methods are being used to measure these levels. In Japan, electrochemiluminescence immunoassay 　(ECLIA) is commonly used, but the upper limit of the reference value for women has not been indicated. The age at which sex differences can be distinguished is also unknown, since the age of puberty has not been measured for both sexes. 　(Methods) The results are represented by age for 1524 boys and 705 girls between 11 and 18 years of age who were measured after 2017, when the method was changed to one with increased accuracy in the low concentration range. (Results) The mean±SD for the 705 girls was 27.7±11.3ng/dL, with a 95th percentile value of 48.4ng/dL and a maximum value of 119.2ng/dL. The 25th percentile value for boys at age 14 was 175.9ng/dL. (Discussion) None of the girls exceeded the 144ng/dL. The distribution of boys was clearly different from that of girls after the age of 14, and it was considered possible to separate the sexes by the detection sensitivity of the ECLIA.