“We’re all in this together”: patient and public involvement and engagement in developing a new psychosocial intervention for adults with an intellectual disability who display aggressive challenging behaviour

Background: Although there is consensus regarding the added value of adults with an intellectual disability and family carers as Patient and Public Involvement and Engagement (PPIE) members in research studies, there is limited reporting on the practice and impact of their involvement. Methods: PPIE input was integral to the application process and subsequent research activities in the NIHR-funded PETAL (PErsonalised Treatment packages for Adults With Learning disabilities) programme. We also conducted semi-structured interviews with five researchers/PPIE facilitators and four family carers, and a focus group with three adults with an intellectual disability who are members of the programme advisory groups. The GRIPP2 checklist guided the reporting of PPIE activities. Results: Thematic analysis identified four overarching themes: (a) Motivation for being a PPIE member, (b) Added value of PPIE input into research (c) Logistics and practicalities of PPIE activities, and (d) Insights and reflections. Family carers highlighted the benefit of giving a voice to adults with an intellectual disability in PPIE activities within research. Both PPIE groups were positive about being able to share their thoughts and feelings with the PETAL research team and making valued contributions to research activities. All stakeholders highlighted the importance of accessible meeting formats to facilitate PPIE activities. They also reflected on how meaningful collaboration could enhance research in the field of intellectual disability. Researchers raised the need for greater diversity within PPIE groups. Conclusions: Future work should aim to further develop PPIE processes and identify strategies to maximise the diversity and inclusion of adults with an intellectual disability and family carers in research advisory groups.