Cystic fibrosis (CF) is an inherited condition, affecting approximately 150 000 people worldwide. Physical activity (PA) is an integral component in the management of CF. However, it is estimated that only a third of young people (with and without CF) achieve UK Chief Medical Officer guideline recommended levels of activity. The aim of this research was to use the person-based approach to develop an intervention supporting families with young people (aged 6–12 years) with CF to incorporate PA as a sustainable habit in their lives to increase the likelihood of sustained PA levels going into adolescence and adulthood.

Using the person-based approach, intervention content was created and iteratively adapted. This was initially guided by relevant literature; the guiding principles, logic model and preliminary content were developed via co-production with patient and public involvement (PPI) representatives (n=8) with lived experience of CF. The intervention was further refined/optimised using qualitative think-aloud and retrospective interviews, the results of the preliminary evaluation are reported. Think-aloud interviews were rapidly analysed using a table of changes analysis and used to inform adaptations to content. Retrospective interviews were analysed thematically.

Community settings in the UK.

Participants included six families with a child with CF aged between 6 years and 12 years old.

Intervention content consisted of nine sections and was delivered as a printable PDF file. Informed by the Capability, Opportunity, Motivation and Behaviour framework and self-determination theory, content focused on promotion of PA as a family activity that is fun, enjoyable, quick and achievable. It promoted ‘movement to make you feel good"’ and in short bursts of activity. Promotion of PA as medicine was avoided. The final intervention was considered to be engaging and acceptable.

Qualitative methods and PPI facilitated the development of a family-focused intervention supporting the integration of PA into daily life. This was viewed as acceptable and engaging among families of people with CF. Future research now needs to explore the effectiveness of the intervention for increasing PA behaviour.