Compatibility between ICD-9 and DSM-III classification of endogenous depression (melancholia).

The classification of depressive disorders (subtypes of Major Depressive Episode--MDE) according to DSM-III is different in many respects from the classification according to ICD-9; the relevance of both diagnostic systems necessitates the assessment of their compatibility. In a sample of 173 depressed inpatients, both diagnostic systems are applied independently and the relationship between affective psychosis (endogenous depression) (ICD-9) and subtypes of MDE (DSM-III) is investigated. The resulting low rate of agreement between endogenous depression (ICD-9) and MDE with melancholia (DSM-III) can be improved considerably by a modification of the diagnostic algorithms applied in DSM-III. Furthermore, by combining the subtype or criteria of melancholia (DSM-III) and characteristics of course (recurrence, bipolarity) the ICD-9 diagnosis of endogenous depression can be simulated.