It is estimated that 32 to 35 million adults in the United States experience an episode of major depressive disorder during their lifetime. When depressed patients present to their healthcare provider for treatment, outcomes are often less than satisfactory. For patients who, despite treatment, continue to suffer from depression, a modest 22%-30% will achieve remission.

Treatment resistance depression can have a severe impact on patient quality of life, and in certain circumstances, may lead to suicide. As well as the burden on time and other resources spent recognizing and diagnosing its etiology, outcomes for those patients with TRD who are not appropriately treated or referred may be adversely affected. Successful recognition, diagnosis, and management of depression is associated with better patient outcomes, and ultimately in savings of both clinic time and resources.