The overall aim of this study is to develop and test a tailored Internet-delivered psychological treatment for patients with mild to moderate major depression and comorbid anxiety symptoms and compare its efficacy to a non-tailored treatment and to an active control group.

Internet-delivered cognitive behaviour therapy (CBT) has emerged as a promising way to administer evidence-based psychological treatments. Mild to moderate major depression has previously been found to treatable via the Internet, with the provision that minimal therapist guidance is given. However, previous research has not taken the issue of comorbidity into account. It is well known that major depression often is accompanied by anxiety and in addition the symptom profile in major depression may differ substantially. The idea behind the proposed research is to tailor the Internet intervention according to the symptom profile. By used a large set of treatment modules (text-based) we aim to diagnose and then prescribe modules. In a randomized trial we want to compare this procedure (e.g., tailored CBT) with the standard Internet-delivered CBT. We will also include a control group in the form of a supervised online discussion group who will later receive CBT.

Inclusion Criteria:

• Clinical diagnosis of Major Depressive Disorder
• 15 or more on MADRS-S

Exclusion Criteria:

• Severe depression (more than 35 on MADRS-S or based on interview)
• Severe psychiatric condition (e.g. psychosis or bipolar disorder)
• Changed medication during the last three months