Recent advances in routine thyroid function testing

Thyroid function tests are one of the most common of endocrine laboratory investigations requested by general clinicians. The tests used therefore have to be efficient at identifying thyroid disease, monitoring treatment, and handling large numbers of tests. Recent advances in methodology have expanded both the range of in vitro thyroid function tests available and the techniques by which the well-established tests may be performed. This article reviews the methods and analytical and clinical performance of the routine tests currently available, concentrating particularly on the relatively new ones, and speculating on their role in strategies for the laboratory investigation of thyroid function.