[Minor depression--how useful and valid a diagnostic concept]

Recent classification research has shown, that there is a great number of mildly depressed patients, who do not fit into the more severe diagnostic criteria of major depression. We therefore asked whether it is necessary to introduce a diagnostic category of minor depression below that of major depression. Using a large outpatient sample, we studied whether such a diagnosis of minor depression would reach sufficient validity according to a variety of independent validation criteria. The results were not very convincing. We therefore discuss alternative definitions of mild depression.