Free Thyroxine T4 Test. Free thyroxine test usually performed along with a tsh test to identify thyroid disorder. Thyroid disorder is the second most common endocrine disease to affect women.
Thyroid disorder is the second most common endocrine disease to affect women. The free t4 test is also termed as ft4 or free t4 index. A free t 4 test is used to find out how well your thyroid gland is working.
Total t4 testing measures the total amount of t4, including free.
Many doctors today use the free t4 test because it's more accurate than the test for bound t4. However, it’s important to note that different labs and doctors may have a varying “normal range.” Also, combining the tsh test along with the ft4 or fti gives an accurate idea about thyroid gland functioning. Free thyroxine is a better indicator than total t4 in that it is not affected by levels of t4 binding proteins.
