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PURLS: It's time to reconsider early-morning testosterone tests
Natalie Long1, Liz Nguyen2, James Stevermer1
1Department of Family and Community Medicine, University of Missouri-Columbia, MO, USA.
Abstract:
Guidelines recommend collecting an early-morning sample to compensate for the natural diurnal variation in testosterone levels. But for men 45 and older, this is unnecessary. Because the natural diurnal variation in testosterone levels tends to diminish with age, it is acceptable to test men ages 45 and older before 2 pm.
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