Test Overview
Test Methodology

Bioavailable Testosterone calculated using the Vermeulen equation.

Reference Range *

Bioavailable Testosterone: Males Ages 20 – 69, 110.0– 400.0 ng/dL; Female Ages 20 – 80, 1.0 – 19.0 ng/dL. All other non-specified age ranges do not have established reference ranges. Refer to Total Testosterone (male, female or pediatric) and Sex Hormone Binding Globulin Handbook entries for reference ranges.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details
Days Set Up
Male: daily; Female and Pediatric: varies; 2-3 times per week
Analytic Time

1 - 4 days

Soft Order Code
TTBSM (Male)/TTBSP (Pediatric and Female)
MiChart Code
Bioavailable Testosterone, Males; Bioavailable Testosterone, Pediatrics and
Synonyms
  • TTBS
  • Free Testosterone
  • Testosterone Binding Index
  • FT
  • Bioavailable Testosterone
  • BIOTEST
  • Testosterone, Bioavailable and Total
  • TTBSM
  • TTBSP
Laboratory
Chemical Pathology
Section
Automation
Specimen Requirements
Collection Instructions

Refer to Total Testosterone (male, female or pediatric) and Sex Hormone Binding Globulin Handbook entries. There is no additional specimen required for the Bioavailable Testosterone calculation.
Male: Collect blood in an SST tube. Centrifuge, aliquot serum into a plastic vial, and refrigerate.
Female and Pediatric: Collect blood in a red top tube. Centrifuge, aliquot serum into a plastic vial, and refrigerate

Normal Volume
1 mL serum
Minimum Volume
0.6 mL serum
Additional Information

Panel includes Total Testosterone, Calculated Bioavailable Testosterone and Sex Hormone Binding Globulin.

Billing
CPT Code
TTBSM: 84403, 84270; TTBSP: 84403, 84270
Fee Code
TTBSM: JA038, JA039; TTBSP: KA008, JA039
LOINC
2986-8 Testosterone; 13967-5 Sex Hormone Binding Globulin