T4 is a scheduling slot on Channel 4 (UK) from about 9am to 12pm on Sunday mornings and in school holidays, the "T" nominally standing for Teenager. The slot has a separate station identification on screen graphic from Channel 4 and E4.

GoldBamboo

... Why get tested?
To diagnose hypothyroidism or hyperthyroidism in adults; to screen for hypothyroidism in newborns.

When to get tested?
Usually is ordered in response to an abnormal TSH test result. Commonly performed on newborns.

Sample required?
A blood sample drawn from a vein in the arm.
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Lab Tests Online - more...

T4 or T-4 is used for various purposes as a designation, abbreviation or ide ...
Wikipedia - [full article]

Resources

  • T4 (Lab Tests Online)