Test Code T4TOT T4 (Thyroxine), Total, Serum
Performing Laboratory
NorDx
Specimen Requirements
Draw blood in a plain, red-top tube or serum gel tube. Spin down and send 1 mL (minimum volume: 0.5 mL) of serum refrigerated.
Note: Label specimen with patient’s name (first and last), date of birth, date and time of draw, and phlebotomist’s initials.
Reference Values
Adult: 5.3-12.3 µg/dL
Pediatric:
Ages: 1-3 yrs: 6.8-13.5 µg/dL
Ages: 3-10 yrs: 5.5-12.8 µg/dL
Methodology
Electrochemiluminescence Immunoassay (ECLIA)
Day(s) Test Set Up
Monday through Sunday
Test Classification and CPT Coding
84436