Study: NCT04996433

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: inpatient CBASP individual therapy
Description: During the 5-week inpatient phase I and the 5-week inpatient phase II / dayclinic treatment all patients in this arm will receive 2 individual CBASP therapy sessions (duration: 50 min per session).

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: inpatient CBASP group therapy
Description: During the 5-week inpatient phase I and the 5-week inpatient phase II / dayclinic treatment all patients in this arm will receive 2 CBASP group therapy sessions (duration: 100 min per session).

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: inpatient CBASP nurse contact
Description: During the 5-week inpatient phase I and the 5-week inpatient phase II / dayclinic treatment all patients in this arm will receive 1 CBASP nurse contact (duration: 30 min per session).

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: inpatient CBASP exercise therapy
Description: During the 5-week inpatient phase I and the 5-week inpatient phase II / dayclinic treatment all patients in this arm will receive 1 CBASP exercise therapy (duration: 75 min per session).

Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: outpatient CBASP group therapy
Description: During the 6-week outpatient treatment all patients in this arm will receive 1 CBASP group therapy session (duration: 100 min per session).

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: inpatient BA individual therapy
Description: During the 5-week inpatient phase I and the 5-week inpatient phase II / dayclinic treatment all patients in this arm will receive 2 individual BA therapy sessions (duration: 50 min per session).

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: inpatient BA group therapy
Description: During the 5-week inpatient phase I and the 5-week inpatient phase II / dayclinic treatment all patients in this arm will receive 2 BA group therapy sessions (duration: 100 min per session).

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: inpatient BA nurse contact
Description: During the 5-week inpatient phase I and the 5-week inpatient phase II / dayclinic treatment all patients in this arm will receive 1 BA nurse contact (duration: 30 min per session)

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: inpatient BA exercise therapy
Description: During the 5-week inpatient phase I and the 5-week inpatient phase II / dayclinic treatment all patients in this arm will receive 1 BA exercise therapy (duration: 75 min per session).

Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: outpatient BA group therapy
Description: During the 6-week outpatient treatment all patients in this arm will receive 1 BA group therapy session (duration: 100 min per session).

Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: algorithm-based study medication
Description: All patients will receive an optimized, algorithm-based antidepressant medication following the current S3-Guidelines on Unipolar Depression. In case of nonresponse:~* 1st line dose escalation (if appropriate)~* 2nd line lithium augmentation~* 3rd line augmentation with 2nd generation antipsychotics or evidence-based combinations of antidepressants~* 4th line change of antidepressant.

Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: algorithm-based study medication
Description: All patients will receive an optimized, algorithm-based antidepressant medication following the current S3-Guidelines on Unipolar Depression. In case of nonresponse:~* 1st line dose escalation (if appropriate)~* 2nd line lithium augmentation~* 3rd line augmentation with 2nd generation antipsychotics or evidence-based combinations of antidepressants~* 4th line change of antidepressant.