This study evaluates the feasibility of the Groups for Health (G4H) intervention for adults accessing support for depression in the UK. G4H targets improvements in adults' interpersonal functioning in order to reduce feelings of loneliness. The study will adapt the G4H intervention for delivery to adults seeking treatment for depression in the UK and estimate trial parameters (recruitment, retention, missing data and acceptability) of the adapted intervention, prior to a definitive trial. A mixed methods design of interviews and a single group, pre-post study will be employed.

Background: Loneliness is frequently reported amongst adults with depression. Interventions to reduce loneliness in different populations have shown mixed results. The Groups for Health (G4H) programme has been developed according to the social identity approach within social psychology and has demonstrated preliminary efficacy for reducing loneliness in a proof-of-concept study conducted with Australian student sample. The present study will examine whether G4H can be adapted to suit the needs of a clinical population in the context of UK secondary care services.

Objective: Phase 1 - To adapt the G4H intervention for delivery to adults seeking treatment for depression in the UK. Phase 2: To estimate trial parameters (recruitment, retention, missing data and acceptability) of the adapted intervention, prior to a definitive trial; to optimise the adapted intervention for delivery to adults accessing treatment for depression in the UK; to optimise evaluation procedures (candidate outcome measures)

Trial configuration: sequential exploratory mixed methods design. Phase 1: one-to-one interviews. Phase 2: Activity 1 (intervention), single group, pre-post study. Activity 2 (interviews): one-to-one interviews.

Condition: Depression

Interventions: group-based behavioural programme

Inclusion Criteria:

Phase 1

Service user participants:

• Aged 18-65
• Accessing treatment for depression
• Loneliness: score 6 or above on the University of California Loneliness Scale (UCLA-3) (Hughes et al., 2004)
• Able to speak/read English
• Ability to give informed consent

Staff participants:

- Clinical practitioner with at least 6 months experience of working with people with depression

Phase 2 Activity 1: intervention

• Aged 18-65
• Accessing treatment for depression
• Loneliness: score 6 or above on the University of California Loneliness Scale (UCLA-3) (Hughes et al., 2004)
• Able to speak/read English
• Ability to give informed consent

Activity 2: interviews

- Attended or agreed to attend Phase 2, Activity 1

Exclusion Criteria:

• None