Four definitions of endogenous depression and the dexamethasone suppression test.

We examined the relationship between the DST and 4 definitions of endogenous depression: DSM-III, Feinberg and Carroll, Newcastle and RDC. Endogenous patients had a significantly higher rate of nonsuppression than nonendogenous patients according to the DSM-III and Newcastle definitions but not according to the RDC and Feinberg and Carroll criteria. Moreover, the relationship between the DST and the DSM-III and Newcastle definitions was significant even after individually controlling for age, psychosis and weight loss. We review the literature on the relationship between the DST and the RDC definition of endogenous depression and suggest that interstudy differences in criteria application may be partially responsible for the inconsistent results across studies.