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T4 Free (Free Thyroxine), Serum/Plasma

Test ID: FT4
Orderable by Ontario ND
Test
Specimen
Performance / Interpretation
Interface / Setup

Test

Method

ECLIA

Report Includes

Free T4 (Free Thyroxine)

Specimens

Serum; Plasma (Heparin); Plasma (EDTA)

Test Version

1-Feb-2023

Specimen

Specimens

Serum; Plasma (Heparin); Plasma (EDTA)

Sample Volume

1 mL

Specimen Comment

Barricor™ tube is not acceptable.

Collection & Handling

Handling Information

Store and send cold or frozen.

Stability

Refrigerated 7 days
Frozen 1 Month

Rejection Criteria

Specimen Barricor™ tube

Test Version

1-Feb-2023

Performance / Interpretation

Method

ECLIA

Turnaround Time

2 days

Results

Name Units Reference Range Conversion Factor
Free T4 (Free Thyroxine) pmol/L
  • 0 to < 1 month: 16 - 50
  • 1 to < 12 months: 14 - 22
  • 1 to < 19 years: 13 - 21
  • Male and Female (non-pregnant): 12 - 21
  • Female (pregnant):
  • First trimester: 11 - 19
  • Second trimester: 10 - 17
  • Third trimester: 8 - 15
 ng/dL x 12.9

Test Version

1-Feb-2023

Interface / Setup

HL7 Interface Codes

Order Code Result Codes Units
FT4 20703Free Thyroxine (FT4) pmol/L

Test Version

1-Feb-2023