The goal of this observational study is to learn about how Pristiq is currently being used in general practice and how psychiatrists and primary care physicians currently perceive Pristiq in terms of efficacy, tolerability, and adherence compared to other treatments for major depressive disorder (MDD).

It is retrospective patient chart study among psychiatrists and primary care physicians (PCPs) treating patients suffering from major depressive disorder (MDD). Physicians will be asked general medical questions in order to quantify their prescribing behavior and their perception of treatment performance. A retrospective patient chart review will then be performed and patient data will be collected to document patient characteristics and actual treatment outcomes. Upon qualification, specific instructions for chart review will be provided. Once the identified charts are pulled, the physicians are instructed to continue with the on-line survey. In total, there will be approximately 450 psychiatrists and 450 primary care physicians participating in this trial.

Inclusion Criteria:

• Patients must be adult, diagnosed with major depressive disorder and treated with pharmacotherapy.
• Physicians must be either a psychiatrist or a primary care physician, a prescriber of Pristiq, have at least 3 charts representing the 4 identified patient types, have been in clinical practice between 4 and 35 years, primarily office based (50%+), not participated in a research study relating to antidepressants or antidepressant therapy within the past month, not a consultant or have a professional relationship with a pharmaceutical company other than for clinical trials or speaking engagements, and not be employed by of affiliated with an advertising agency, market research company, or pharmaceutical company.

Exclusion Criteria:

• Patients who have not been treated for depression.

patient charts from psychiatrists and primary care physicians (PCPs) treating patients suffering from major depressive disorder (MDD).