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Test ID BLOD0213 Thyroxine-Binding Globulin (TBG), Serum

Reporting Name

Thyroxine Binding Globulin, S

Useful For

Determination of thyroxine-binding globulin levels is particularly useful for cases in which total thyroid hormone levels do not correlate with the thyrometabolic status, most commonly with pregnancy or the use of contraceptive steroids

Performing Laboratory

Mayo Medical Laboratories in Rochester

Specimen Type


Specimen Required


Preferred: Red top

Acceptable: Serum gel

Specimen Volume: 0.5 mL

Specimen Minimum Volume

0.35 mL

Specimen Stability Information

Specimen Type Temperature Time
Serum Refrigerated (preferred) 7 days
  Frozen  30 days

Reference Values

Males: 12-26 mcg/mL

Females: 11-27 mcg/mL

Day(s) and Time(s) Performed

Monday through Friday; 5 a.m.-12 a.m., Saturday; 6 a.m.-6 p.m.

Test Classification

This test has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
TBGI Thyroxine Binding Globulin, S 3021-3


Result ID Test Result Name Result LOINC Value
TBGI Thyroxine Binding Globulin, S 3021-3

Reject Due To


Mild OK; Gross reject


Mild OK; Gross OK





Method Name

Solid-Phase Chemiluminescent Assay