T4 (THYROXINE), FREE

Test Code

LAB127

CPT Codes
84439

Preferred Specimen

One 4.5 mL light green top tube
Pediatric: One light green top microtainer

Other Acceptable Specimens

Dark green top tube
Red top tube
Gold top tube

Transport Container

Sample must be centrifuged within two hours of collection. Serum/plasma must be removed from the red cells and put into aliquot tubes following centrifugation.

Transport Temperature

Refrigerated

Specimen Stability

Centrifuge within 2 hours after collection
Ambient: 24 hours
Refrigerated: 6 days
Frozen: 6 days

Methodology
Chemiluminescent Immunoassay

Setup Schedule

Sunday-Saturday

Reference Range

Age	Normal Values
0D-3D	0.80-2.80 ng/mL
4D-29D	0.80-2.20 ng/mL
30D-15Y	0.80-1.80 ng/mL
16Y-18Y	0.60-1.70 ng/mL
>=19Y	0.70-1.25 ng/mL

Performing Laboratory
West Virginia University Hospital, Inc.
Berkeley Medical Center
Barnesville Hospital
Braxton County Memorial
Camden Clark Medical Center
Fairmont Medical Center
Garrett Regional Medical Center
Harrison Community Hospital
Jackson General Hospital
Jefferson Medical Center
Princeton Community Hospital
Potomac Valley Hospital
Reynolds Memorial Hospital
Summersville Regional Medical Center
St. Joseph’s Hospital
United Hospital Center
Uniontown Hospital
Wetzel County Hospital
Wheeling Hospital

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.