Specimen should be centrifuged prior to transport. Ensure that complete clot formation in serum specimens has taken place prior to centrifugation. If specimen is centrifuged before a complete clot forms, the presence of fibrin may cause erroneous results
Minimum Volume
1.0 mL whole blood
Stability (from collection to initiation)
Ambient: 5 days
Refrigerated: 7 days
Frozen: 30 days
Ordering Recommendations
Useful for assessing thyroid function and screening individuals for hypothyroidism. Includes reflex to free thyroxine when thyroid stimulating hormone (TSH) results are outside the reference range.
Notes
Reflex Tests:
Free T4
If TSH value is >4.2 or <0.27 mIU/mL then Free T4 will be performed at an additional charge.
Add-On Information
This test may be added to an existing specimen for up to 5 days following collection.
Reference Interval
0.27 - 4.2 IU/L
Note: Free T4 will be performed when TSH is <0.27 or >4.20 mIU/L
Specimen should be centrifuged prior to transport. Ensure that complete clot formation in serum specimens has taken place prior to centrifugation. If specimen is centrifuged before a complete clot forms, the presence of fibrin may cause erroneous results
Minimum Volume
1.0 mL whole blood
Stability (from collection to initiation)
Ambient: 5 days
Refrigerated: 7 days
Frozen: 30 days
Ordering
Ordering Recommendations
Useful for assessing thyroid function and screening individuals for hypothyroidism. Includes reflex to free thyroxine when thyroid stimulating hormone (TSH) results are outside the reference range.
Notes
Reflex Tests:
Free T4
If TSH value is >4.2 or <0.27 mIU/mL then Free T4 will be performed at an additional charge.
Add-On Information
This test may be added to an existing specimen for up to 5 days following collection.
Result Interpretation
Reference Interval
0.27 - 4.2 IU/L
Note: Free T4 will be performed when TSH is <0.27 or >4.20 mIU/L
