Davis’s Laboratory and Diagnostic Tests Online, powered by Unbound Medicine, provides nurses and students access to 400+ test monographs containing reference ranges, indications, patient preparation and result interpretation. Explore these free sample topics:
-- The first section of this topic is shown below --
Free T3, FT3.
A complementary adjunct to evaluate thyroid hormone levels primarily related to hyperthyroidism and to assess causes of hypothyroidism.
Serum collected in a gold-, red-, or red/gray-top tube.
|Age||Conventional Units||SI Units (Conventional Units × 1.54)|
|0–3 d||2–7.9 pg/mL||3.1–12.2 pmol/L|
|4–30 d||2–5.2 pg/mL||3.1–8 pmol/L|
|1–23 mo||1.6–6.4 pg/mL||2.5–9.9 pmol/L|
|2–6 yr||2–6 pg/mL||3.1–9.2 pmol/L|
|7–17 yr||2.9–5.1 pg/mL||4.5–7.8 pmol/L|
|Adults and older adults||2.6–4.8 pg/mL||4–7.4 pmol/L|
|Pregnant women (4–9 mo gestation)||2–3.4 pg/mL||3–5.2 pmol/L|