| Ordering Code | 449 |
|---|---|
| Test Name | TSH / T4, Free |
| Alias | TSH / Free T4 |
| Preferred Specimen | Serum |
| Preferred Container | SST (Gold) |
| Other Specimen/Container | Serum in Plain (Red), Plasma in Lithium Heparin (Green-PST), Plasma in Lithium Heparin (Dark Green-PP No Gel) |
| Optimum Volume | 0.5 mL |
| Handling Instructions | All specimen types must be centrifuged within 2 hours of collection. If no gel separation present in tube and testing is delayed, plasma/serum is aliquoted from cells within 2 hours of collection Keep tubes stoppered at all times. |
| Transport Requirements | Oahu: Refrigerated Airline: Refrigerated |
| Specimen Stability | Ambient: 8 Hours Refrigerated: 48 Hours Frozen: 30 Days Frozen samples should be thawed only once DO NOT use frost-free freezers. |
| Rejection Criteria | Insufficient quantity, Specimen older than stability limits, Wrong specimen type |
| Avail. Stat | NO |
| Analytic Time | 1 Day |
| Methodology | See individual analytes |
Reference range(s)
The reference ranges listed below are valid on this date of August 15, 2025.
| Component | Age | Male Norm | Male Critical Low | Male Critical High | Female Norm | Female Critical High | Female Critical Low | Units | Add'l info |
|---|---|---|---|---|---|---|---|---|---|
| TSH | >=2M | 0.30-4.20 | 0.30-4.20 | uIU/mL | |||||
| TSH | 3D-1M | 0.67-5.57 | 0.67-5.57 | uIU/mL | |||||
| TSH | 2D-3D | 0.83-8.65 | 0.83-8.65 | uIU/mL | |||||
| TSH | 1D-2D | 6.60-15.60 | 6.60-15.60 | uIU/mL | |||||
| TSH | 0-1D | 9.20-28.40 | 9.20-28.40 | uIU/mL | |||||
| T4, Free | ALL | 0.70-1.80 | 0.70-1.80 | ng/dL |