Co-design of a complex school-based intervention for attention deficit/hyperactivity disorder using the Intervention Mapping approach.

Background: Attention deficit/hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental condition, comprising varying difficulties in attention and/or impulsive and overly active behaviours, with knock on effects for health, learning, social and emotional functioning, self-esteem and quality of life. There is little implementation of school-based intervention for ADHD in UK mainstream primary schools, due to resource constraints and implementation challenges of existing, multi-component complex interventions. Methods: This study describes the co-design of a novel, personalised school-based intervention for ADHD, delivered by teachers to primary school students. The Intervention Mapping approach was used to structure intervention development. Co-design with a Planning Group of 33 adults and children with ADHD, school and health professionals is described in detail, as well as an overview of the resultant intervention: the Flex toolkit. Results: Co-design was woven throughout the intervention development and evaluation process, leading to a novel digital health intervention for ADHD suitable for delivery in UK mainstream school settings, by classroom teachers. The Flex toolkit contains some core components applicable to every child, then becomes personalised depending on each child's areas of strength and challenge. Conclusion: This novel digital intervention builds on the existing evidence base whilst ensuring that the content, format and design as well as implementation and evaluation plan are suitable for the UK mainstream primary school context.