Introduction: Health, social care, charitable and justice sectors are increasingly recognising the need for trauma-informed services that seek to recognise signs of trauma, provide appropriate paths to recovery, and ensure that services enable people rather than re-traumatise. Foundational to the development of trauma-informed services is collaboration with people with lived experience of trauma. Co-production principles may provide a useful framework for this collaboration, due to their emphasis on lived experience, and intent to address power imbalances and promote equity. This article aims to examine trauma-informed and co-production principles to consider the extent to which they overlap and explore how to tailor co-production approaches to support people who have experienced trauma. Methods: Bridging Gaps is a collaboration between women who have experienced complex trauma, a charity that supports them, primary care clinicians and health researchers to improve access to trauma-informed primary care. Using co-production principles, we aimed to ensure that women who have experienced trauma were key decision-makers throughout the project. Through reflective notes (n=19), observations of meetings (n=3), interviews with people involved in the project (n=9) and reflective group discussions on our experiences, we share learning, successes and failures. Data analysis followed a framework approach, using trauma-informed principles. Results: Co-production processes can require adaptation when working with people who have experienced trauma. We emphasise the need for close partnership working, flexibility, and transparency around power dynamics, paying particular attention to aspects of power that are less readily visible. Sharing experiences can re-trigger trauma. People conducting co-production work need to understand trauma and how this may impact upon an individual's sense of psychological safety. Long-term funding is vital to enable projects to have enough time for establishment of trust and delivery of tangible results. Conclusions: Co-production principles are highly suitable when developing trauma-informed services. Greater consideration needs to be given as to whether and how people share lived experiences, the need for safe spaces, honesty and humility, difficult dynamics between empowerment and safety, and whether and when blurring boundaries may be helpful. Our findings have applicability to policy-making, funding and service provision to enable co-production processes to become more trauma-informed.

Maria Carvalho and Florrie Connell worked for One25 at the time of this project. One25 received a fee to compensate the charity for the time that their staff committed to the project.

Bridging Gaps has been funded through the Q Exchange by the Health Foundation and NHS England and NHS Improvement. It has also been funded by National Institute for Health and Care Research (NIHR) Research Capability Funding through the NHS Bristol, North Somerset and South Gloucestershire CCG. It has also been funded by the Co-Production Collective (formerly UCL Centre for Co-production in Health Research) as part of the 2019/20 Phase 2 Pilot Projects and by the NIHR School for Primary Care Research (grant ref 465). This research was supported by the NIHR Applied Research Collaboration (ARC West) at University Hospitals Bristol and Weston NHS Foundation Trust. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

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The Faculty of Health Sciences Research Ethics Committee of the University of Bristol gave ethical approval for this work, references 93802 and 110882.

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Original data are not available due to the potential to compromise people's anonymity and the small number of interviews that were undertaken.