The guideline recommends doctors investigating a patient's thyroid functioning begin by ordering only the sensitive thyroid stimulating hormone (sTSH) test. It advocates its use as the first diagnostic test of choice because of its high sensitivity and specificity and its ability to accurately diagnose both hyper- and hypo-thyroidism. Prior to the guidelines, doctors frequently ordered three different thyroid tests simultaneously: the sTSH, the total thyroxine (TT4), and the total triiodothyronine test (TT3).
The guideline also recommended all labs in the province adopt a reflex testing protocol for thyroid testing.
