To explore the acceptability of the Community Outpatient Psychotherapy Engagement Service for Self-harm (COPESS) intervention and trial procedures for participants.

A mixed-method approach and a single-blind randomised controlled trial design with 1:1 allocation to either COPESS plus treatment as usual or treatment as usual alone.

Primary care.

Fifteen semistructured interviews were conducted with participants in the COPESS trial; eight were randomised to the intervention arm, and seven were randomised to the treatment-as-usual arm. Interviews lasted 30–60 min.

COPESS is a brief, relational psychotherapy delivered over 4 weekly sessions plus a follow-up, focusing on understanding difficult emotional states and their links to self-harm through here-and-now relational and emotional processes.

Thematic analysis allowed exploration of themes important to participants in their experiences in the COPESS trial and their experiences of care for self-harm more generally.

Five themes were identified as associated with the acceptability of the COPESS intervention and trial: self-harm as a primary problem, what I needed when I needed it, being heard and understood, online delivery of the intervention and lasting impacts. Participants generally expressed positive views about the intervention, citing a need for services that specifically target self-harm and an appreciation of the rapid access to help. Strong relationships with the therapist were highly valued and not diminished by online delivery of the intervention. Positive impacts continued post therapy sessions.

These results support the acceptability of the COPESS intervention, the need for self-harm specific services and support moving forward to a full trial.

Pre-registered on clinicaltrials.gov (NCT04191122) on 9 December 2019.