Amajor depressive episode requires of nine symptoms, including a depressed mood and/or diminished interest in activities for at least two weeks.

Requires five of nine symptoms. According to the DSM-V to be able to diagnose certain mental disorders the person must present a certain number of symptoms or diagnostic criteria. In the case of depression the person must present 5 symptoms, including depressive mood, in order to provide the diagnosis, otherwise, the diagnosis would be ruled out.

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