T4 (THYROXINE), TOTAL

Test Documentation
Specimen Required
Draw blood in a SST. Centrifuge, separate and send 1.0 mL serum (0.5 mL minimum) refrigerated in a screw-capped plastic vial.

Alternate Specimen
Serum: Red-top

Rejection Criteria
Grossly hemolyzed or grossly lipemic specimens
Plasma

Methodology
Chemiluminescence

Stability
Room Temperature: 8 hours; Refrigerated: 72 hours; Frozen: 14 days

Reference Range
Age   Reference range  
1-23 months   6.0-13.2 µg/dL  
24 months (2 years)-12 years   5.5-12.1 µg/dL  
13 years-20 years   5.511.1 µg/dL  
21 years and above   4.5-10.9 µg/dL  

Performed
Monday-Friday

Turnaround Time3 days
Test CodeT4
CPT-4 Code (s)
84436
LOINC Codes
3026-2

Warde
Medical
Laboratory