Test Code T4F FREE T4
Additional Codes
N.FREET4
Methodology
Automated Chemistry Analyzer
Specimen Requirements
Specimen Type: Serum or Plasma
Container/Tube: SST or Lithium Heparin
Acceptable: Red top
Specimen Volume: 1 mL (minimum 0.5)
Collection Instructions:
- Allow specimen to clot completely if a serum tube (SST) was used.
- Separate serum (SST) or plasma (Lithium Heparin) from cells within 24 hours and transport refrigerated. If red top tube is collected, separate serum from cells within 2 hours and place in separate plastic tube.
- Properly label tube with patient's name, DOB, requisition number and type of tube, i.e. LiHep or NaHep etc.
Specimen Transport/Stability
Refrigerated: 24 hours on gel, 6 days poured off
Maximum Laboratory Time
24 to 48 hours
Reference Ranges
Free T4 | ng/dL |
Newborn | 0.70 - 2.20 |
18 yrs | 0.70 - 1.48 |
Day(s) Test Set Up
Daily
Test Classification and CPT Coding
84439