Testosterone Free, Calculation

Test Code

18944

CPT Code(s)

84402

Test Code

18944

CPT Code(s)

84402

Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide SERVICE AREA INFORMATION to find available tests you can order.

In-home collection may be available in your area for purchase through Quest Mobile.

Clinical Significance

Testosterone Free, Calculation - This test may aid in the diagnosis of hypogonadism in men, especially when total testosterone level is near the lower limit of the normal range or when sex hormone-binding globulin (SHBG) concentrations are affected by certain conditions. This test may also aid in the diagnosis of hyperandrogenemia in women [1-3].

Testosterone circulates in 3 major forms: unbound (free), weakly bound to albumin, and tightly bound to SHBG. Free testosterone comprises 2% to 4% of total testosterone and is biologically active. In this panel, free testosterone concentration is calculated based on measurements ...

Test Resources

Test FAQ

STRENSIQ® (Asfotase Alfa) Assay Interference

Test Details

Methodology

Chromatography/Mass Spectrometry • Calculation (CALC) • Immunochemiluminescence Assay (ICMA)

Assay Category

This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Reference Range(s)

	Male (pg/mL)	Female (pg/mL)
<1 Year	Not established	Not established
1-11 Years	≤1.3	≤1.5
12-13 Years	≤64.0	≤1.5
14-17 Years	4.0-100.0	≤3.6
18-69 Years	46.0-224.0	0.2-5.0
70-89 Years	6.0-73.0	0.3-5.0
>89 Years	Not established	Not established

LOINC® Codes, Performing Laboratory

Service Area must be determined

Methodology

Chromatography/Mass Spectrometry • Calculation (CALC) • Immunochemiluminescence Assay (ICMA)

Assay Category

Reference Range(s)

	Male (pg/mL)	Female (pg/mL)
<1 Year	Not established	Not established
1-11 Years	≤1.3	≤1.5
12-13 Years	≤64.0	≤1.5
14-17 Years	4.0-100.0	≤3.6
18-69 Years	46.0-224.0	0.2-5.0
70-89 Years	6.0-73.0	0.3-5.0
>89 Years	Not established	Not established

LOINC® Codes, Performing Laboratory

Service Area must be determined

Preferred Specimen(s)

2.8 mL serum

Alternative Specimen(s)

Plasma collected in: Sodium heparin (green-top) tube or lithium heparin (green-top) tube

Minimum Volume

1.3 mL

Collection Instructions

Specify age and sex on test request form.

Red-top tube (no gel): Allow blood to clot at room temperature. Centrifuge to separate the serum from the cells and immediately pour serum into a plastic transport tube.
Serum separator tube: Allow blood to clot at room temperature, centrifuge, and remove serum from the gel immediately (not to exceed 48 hours) by pouring serum into a plastic transport tube.

Transport Container

Transport tube

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 7 days
Refrigerated: 7 days
Frozen: 2 years

Reject Criteria

Gross hemolysis • Grossly lipemic

Setup Schedule

Service Area must be determined

Preferred Specimen(s)

2.8 mL serum

Alternative Specimen(s)

Plasma collected in: Sodium heparin (green-top) tube or lithium heparin (green-top) tube

Minimum Volume

1.3 mL

Collection Instructions

Transport Container

Transport tube

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 7 days
Refrigerated: 7 days
Frozen: 2 years

Reject Criteria

Gross hemolysis • Grossly lipemic

Setup Schedule

Service Area must be determined

Not offered in Quest Diagnostics Nichols Institute (IFD) – San Juan Capistrano. Please provide SERVICE AREA INFORMATION to find available tests you can order.

In-home collection may be available in your area for purchase through Quest Mobile.

Test Details

Clinical Significance

Test Resources

Reference ranges are provided as general guidance only. To interpret test results use the reference range in the laboratory report.

The CPT codes provided are based on AMA guidance and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

This material contains content from LOINC® (http://loinc.org). The LOINC Table, LOINC Table Core are copyright © 1995-2019, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license at http://loinc.org/license.

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