Special Communication
June 2022: Changes to Testosterone, Total and Free, Serum (TFTEST)
Effective June 30, 2022
Testosterone, Total and Free, Serum (TFTEST)
Changes to Specimen Requirements
Specimen Type:
Serum
Volume:
2.5 mL
Minimum Volume:
1 mL
Collection Container:
Red (Serum) No Additive Tube
Transport Temperature:
Refrigerated
Do not draw serum gel tubes for this test.
Changes to Reference Ranges
Male
1 to 8 Years:
<0.13 ng/dL
9 Years:
<0.13 – 0.45 ng/dL
10 Years:
<0.13 – 1.26 ng/dL
11 Years:
<0.13 – 5.52 ng/dL
12 Years:
<0.13 – 9.28 ng/dL
13 Years:
<0.13 – 12.6 ng/dL
Female
1 to 15 Days:
<0.13 – 0.25 ng/dL
16 to 364 Days:
Values decrease gradually from newborn (<0.13 – 0.25 ng/dL) to prepubertal levels.
*Citation: J Clin Endocrinol Metab 1973;36(6):1132-1142.
1 to 4 Years:
<0.13 ng/dL
5 Years:
<0.13 ng/dL
6 Years:
<0.14 ng/dL
7 Years:
<0.13 – 0.23 ng/dL
8 Years:
<0.13 – 0.34 ng/dL
9 Years:
<0.13 – 0.46 ng/dL
10 Years:
<0.13 – 0.59 ng/dL
11 Years:
<0.13 – 0.72 ng/dL
12 Years:
<0.13 – 0.84 ng/dL
13 Years:
<0.13 – 0.96 ng/dL
14 Years:
<0.13 – 1.06 ng/dL
15 to 18 Years:
<0.13 – 1.09 ng/dL
19 Years:
<0.13 – 1.08 ng/dL
20 to 24 Years:
<0.13 – 1.08 ng/dL
25 to 29 Years:
<0.13 – 1.06 ng/dL
30 to 34 Years:
<0.13 – 1.03 ng/dL
35 to 39 Years:
<0.13 – 1.00 ng/dL
40 to 44 Years:
<0.13 – 0.98 ng/dL
45 to 49 Years:
<0.13 – 0.95 ng/dL
50 to 54 Years:
<0.13 – 0.92 ng/dL
55 to 59 Years:
<0.13 – 0.90 ng/dL
60 to 64 Years:
<0.13 – 0.87 ng/dL
65 to 69 Years:
<0.13 – 0.84 ng/dL
70 to 74 Years:
<0.13 – 0.82 ng/dL
75 to 79 Years:
<0.13 – 0.79 ng/dL
80 to 84 Years:
<0.13 – 0.76 ng/dL
85 to 89 Years:
<0.13 – 0.73 ng/dL
90 to 94 Years:
<0.13 – 0.71 ng/dL
95 to 100 Years:
<0.13 – 0.68 ng/dL