Free T4
Specimen Requirements
Specimen Type: Blood
Container/Tube:
Preferred: Light-green top (lithium heparin gel)
Acceptable: Red top, serum gel
Specimen Volume: Full tube
Specimen Minimum Volume: 2 mL
Collection Instructions:
1. Send specimen in original tube.
2. If there is a delay in transport of >1 hour, centrifuge tube.
Stability
7 days Refrigerated
Reference Range
0.76-1.46 ng/dL
Instrumentation
Siemens Dimension EXL
Methodology
Enzyme Immunoassay (EIA)
Test Schedule/Analytical Time/ Test Priority
Daily / Same day / Available STAT
CPT (s)
84439