Organization (Year) Testing Requirement Diagnostic Threshold and Notes Endocrine Society (2018) Fasting total testosterone measured on 2 separate mornings, both unequivocally low, plus consistent symptoms or signs Lower limit 264 ng/dL (CDC-standardized assays). Measure free testosterone if SHBG may be altered (obesity, diabetes) or total testosterone is borderline American Urological Association (2018) Total testosterone measured on 2 separate early mornings, both low (Strong Recommendation, Grade A) Consistently