Depression affects hundreds of millions of people around the world. It occurs along a continuum of severity that ranges from relatively mild episodic states of depressed mood to serious, long-term depressive symptoms that can greatly impact the quality of a person’s life. Major depression negatively impacts how someone thinks, feels, and acts and is characterized by feelings of sadness or loss of interest in activities that they once enjoyed.
The Depression Anxiety Stress Scale (DASS-21) is a well-established, self-administered instrument with 21 statements that help people define, understand, and measure clinically significant emotional states.
Persistent depressive disorder (PDD), also called dysthymia, is a low-level, chronic form of depression. Because this condition is ongoing, people with PDD tend to have no positive emotional point of reference for comparison and therefore may view their constant, low levels of depression as normal.