The purpose of this retrospective observational study is to evaluate the characteristics of patients receiving Seroquel XR as treatment for their Major Depressive Disorder. The study will also investigate how the medication is used for these patients and if there are any differences in drug utilisation between the included countries. The study is observing patients initiating Seroquel XR during a 9 month period corresponding to 3 to 12 months following the launch of the product in each country for the MDD indication. A drug utilisation questionnaire will be used to collect study data from patients' medical records.

A Multinational, Multicenter, Retrospective, Observational Drug Utilisation Study of Seroquel Extended Release (XR) Prescribed by Psychiatrists as Treatment for Major Depressive Disorder (MDD) in Selected Countries in the European Union (EU)

Inclusion Criteria:

• Provision of informed consent before initiation of any collection of questionnaire data.
• Documented clinical diagnosis of Major Depressive Disorder, Single Episode, or Recurrent.
• Initiation of Seroquel XR for treatment of MDD during the period defining the inception cohort, i.e. from 3 months after launch until the index date (12 months after launch).

Exclusion Criteria:

• If participating in any clinical trial during the time from 3 months after launch until the index date, the patient cannot take part in this study.

500-2000 patients that are broadly representative of the overall Major Depressive Disorder population in Europe. Patients are distributed at medical healthcare centres, private practice, as well as university and community hospitals in five European countries.