Persistent depressive disorder, known as dysthymia or low-grade depression, is less severe than major depression but more chronic. It occurs twice as often in women as in men.

With fewer symptoms and less severe presentation, persistent depressive disorder (PDD) differs from clinical depression. If ...

Dr. Alessandri answers the question: 'PDD-NOS vs. Pervasive Dev. Disorder?' Oct. 23, 2008 -- Question: How does PDD-NOS differ from pervasive developmental disorder? Answer: PDD-NOS differs ...