Objective: This study investigated the feasibility of a novel blended (face-to-face and computer-based) group intervention for the reduction of depressive symptoms in major depression.

Design: Patient-centred uncontrolled interventional study.

Setting: University setting in a general community sample. A multimodal recruitment strategy (public health centres and public areas) was applied.

Participants: Based on independent interviews, 26 participants, diagnosed with major depressive disorder (81% female; 23% comorbidity >1 and 23% comorbidity >2), entered treatment.

Intervention: Acceptance and mindfulness based, as well as self-management and resource-oriented psychotherapy principles served as the theoretical basis for the low-threshold intervention. The blended format included face-to-face sessions, complemented with multimedia presentations and a platform featuring videos, online work sheets, an unguided group chat and remote therapist-patient communication.

Main outcome measures: The Center for Epidemiological Studies-Depression scale and the 12-item General Health Questionnaire.

Results: Large to very large within group effect sizes were found on self-reported depression (F_{(2, 46.37)}=25.69, p<0.001; d=1.80), general health (F_(2,46.73)=11.47, p<0.001; d=1.32), personal resources (F_(2,43.36)=21.17, p<0.001; d=0.90) and mindfulness (F_(2,46.22)=9.40, p<0.001; d=1.12) after a follow-up period of 3 months. Treatment satisfaction was high, and 69% ranked computer and multimedia use as a therapeutic factor. Furthermore, participants described treatment intensification as important advantage of the blended format. Half of the patients (48%) would have preferred more time for personal exchange.

Conclusion: The investigated blended group format seems feasible for the reduction of depressive symptoms in major depression. The development of blended interventions can benefit from assuring that highly structured treatments actually meet patients' needs. As a next step, the intervention should be tested in comparative trials in routine care.

Trial registration number: DRKS00010894; Pre-results.