• The primary outcome measure used is the MADRS (Montgomery-Asberg Depression Rating Scale). At study end response criteria is defined as a 50% reduction in total MADRS score and remission defined as less or equal to 10.
  

• Other outcome measures administered fortnightly are: BPRS (Brief Psychiatric Rating Scale), CORE (measure of melancholic symptoms), BDI (Beck Depression Inventory), CGI (Clinical Global Impression Scale), GAF (Global Assessment of Functioning Scale).
  

The primary outcome measure used is the MADRS (Montgomery-Asberg Depression Rating Scale). This is administered at baseline and on a fortnightly basis. At study end response criteria is defined as a 50% reduction in total MADRS score and remission defined as a MADRS score of less than or equal to 10.

Other outcome measures administered fortnightly are: BPRS (Brief Psychiatric Rating Scale), CORE (measure of melancholic symptoms), BDI (Beck Depression Inventory), CGI (Clinical Global Impression Scale), GAF (Global Assessment of Functioning Scale). A cognitive battery is also administered.

Inclusion Criteria:

• Moderate to severe depressive symptoms as indicated as MADRS >20
• Failure to respond to a minimum of two antidepressant medications
• No increase or initiation of new antidepressant therapy in the four weeks prior to entering the trial Exclusion Criteria
• Have an unstable medical condition, neurological disorder or any history of seizure disorder or are currently pregnant or lactating
• Previous brain injury or surgery, any metal clips, plates or other metal items in the head, cardiac pacemaker
• In the opinion of the investigator, are a sufficient suicide risk to require immediate electro-convulsive therapy
• Have a current DSMIV diagnosis of substance abuse or dependence disorder, a diagnosis of a personality disorder or another axis 1 disorder