Determining what constitutes a low level of testosterone is a major point of confusion in the field of testosterone deficiency — also known as hypogonadism. A recent article adds to the controversy by proposing a new, lower threshold for normal testosterone concentrations on the basis of harmonized reference ranges.
Refers to Travison, T. G. et al. Harmonized reference ranges for circulating testosterone levels in men of four cohort studies in the USA and Europe. J. Clin. Endocrinol. Metab.http://dx.doi.org/10.1210/jc.2016–2935 (2017)