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Test Code T4 T4 (Thyroxine), Total, Serum

Additional Codes

LAB126

Collection Method

Venous collection

Minimum Volume

0.5ml

Container

Gold Top SST

Acceptable Specimens

Serum:

  • Gold Top SST
  • Red Top


Plasma:

 

  • Light Geen Top (lithium heparin)

Reference or Target Ranges

Age Male Female
< 5 days 5.0 - 18.5 5.0 - 18.5
6 days to 2 months 5.4 - 17 5.4 - 17
3 months to 1 year 5.7 - 16 5.7 - 16
> 1 year 4.5 - 11 4.5 - 11

 

Reportable Units

ng/ml

Critical Value

Not defined for this assay

Reasons for Rejection

Hemolysis Threshold 2300 mg/dL
Icterus Threshold 37 mg/dL
Lipemia Threshold 2500 mg/dL
Other QNS, contaminated, improperly Labeled, improper specimen type

Specimen Stability

Ambient 8 hours
Refrigerated (4°C to 8°C) 7 days
Frozen(-40°C to 0°C) 30 days

Performance Information

Days and Time Performed 24/7
Expected Turn Around Time Routine: 4 hours
Stat Availability No
Performing Bench CPH Chemistry
Methodology/Method Description Roche Cobas

CPT Codes

84436

Last review/edit date

March 2024