Test Code T4F Thyroxine (T4), Free, Serum
Additional Codes
Software | Test Code |
---|---|
Label Text | T4F |
EPIC | LAB127 |
Performing Laboratory
NorDx Laboratories
Useful For
Obtaining a more accurate assessment of thyroid status in patients with abnormal T4-binding protein levels including those who are pregnant or receiving steroid therapy
Method Name
Electrochemiluminescent Immunoassay (ECLIA)
Reference Values
0.93 - 1.7 ng/dL
T4 Free may be artificially elevated by heparin.
Days and Times Test Performed
Monday through Sunday
Report Available
1 Day
Specimen Type
Serum
Preferred Container
Serum Separator Tube (SST)
Preferred Volume
Serum: 1 mL (Serum Separator Tube (SST))
Minimum Volume
Serum: 0.5 mL (Serum Separator Tube (SST))
Specimen Collection and Handling
Spin specimen, separate from clot and send refrigerated.
Specimen Stability Information
Specimen Type: Serum
Frozen: 1 Month
Refrigerated: 7 Days
Must be spun/separated within: 2 Hours
Add On Capable
Yes
Advance Beneficiary Notice Requirements
This test, when ordered on Medicare patients, is subject to the National Coverage Determination (NCD) policies. Please verify that the diagnosis code (ICD code) you have chosen demonstrates medical necessity for the test as documented in the physician’s patient record. The CMS web site is available to assist you with this verification. A properly executed Advance Beneficiary Notice (ABN) must be submitted with the specimen if medical necessity is not demonstrated by the ICD code chosen.
CPT Code Information
CPT Code |
CPT Description |
CPT Disclaimer |
---|---|---|
84439 | Thyroxine, Free, Quantitative |
Keywords
FREE T4 (THYROXINE)
NON-PROTEIN BOUND TETRAIODOTHYRONINE
T4 (THYROXINE) FREE
THYROXINE
THYROXINE (T4), TOTAL OR FREE
Performing Laboratory Location
NorDx Laboratories
LOINC Code Information
3024-7
Acceptable Alternative Container(s)
Plasma Separator Tube (PST)
Red Top Tube