The dialogue presented in these letters is representative of the continuing interest regarding methodologies and the diagnostic utility of the DST. The basic statistical and conceptual issues involved in either diagnostic or screening tests, including the concepts of sensitivity and specificity, are well described and summarized in this issue in the PERSPECTIVES article by Baldessarini et al (p 569). The emerging data on the DST and other indices of endocrine dysfunction in the affective disorders (as well as other illnesses) should eventually clarify their clinical utility in practice and the pathophysiology of the altered endocrine responses. Meanwhile, we need to keep in mind that endocrine dyscontrol is not necessarily identical with the pathophysiologic "essence" (or locus) of endogenous depression.
Furthermore, in psychiatry, as in all of medicine, diagnostic judgment can be guided but not replaced by any laboratory test, no matter how much we might wish for "objective" tests