Test Directory
| Test Code | ||
| FT4 | ||
| Test Name | ||
| T4, Free | ||
| CPT Codes | ||
| 84439 | ||
| Expected Turnaround Time | ||
| 1 day | ||
| Clinical Utility | ||
| Used in the evaluation of thyroid function and thyroid disorders. | ||
| Specimen and Container Info | ||
|
Specimen Types: Serum or Plasma Collection Containers:
Minimum Acceptable Volume: 0.8 mL |
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| Processing and Submission Instructions | ||
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Separator tubes: Contains clot activator and gel for separating serum from cells, but not anticoagulant. Separate serum from cells as soon as the clot has formed (30 minutes). If specimen is centrifuged before clotting is complete, a fibrin clot will form on top of the cell. This may cause the gel barrier to not be intact and could cause improper separation of serum and cells, possibly affecting test results. |
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| Transport Instructions | ||
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Transport to the laboratory refrigerated. |
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| Stability Requirements | ||
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| Methodology | ||
| Chemiluminescent Immunoassay | ||
| Reference Intervals | ||
| Performing Location | ||
| Roble Road Core Laboratory | ||
| Testing Schedule | ||
| Routine, daily | ||
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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