Is it true that a lavender tube is necessary for drawing thyroid function tests (TFT)?

The statement that a lavender tube is necessary for drawing thyroid function tests (TFT) is false. In practice, a lavender tube, which typically contains EDTA as an additive for hematology tests, is not the appropriate choice for drawing specimens for thyroid function tests. TFTs are generally drawn in either a plain red-top tube, which allows the blood to clot and then separates the serum, or in a serum separator tube (SST), which contains a gel that facilitates the separation of serum after centrifugation.

This distinction is important because using the correct type of collection tube ensures the integrity of the sample and accurate test results. Other tube types, such as those with additives unsuitable for hormone testing, can interfere with the analysis, leading to inaccurate measurements of thyroid hormones. Therefore, a lavender tube is not essential nor recommended for TFTs, making the statement incorrect.