Impactful co-design: Adult decision-makers' perspectives on actualising children's ideas for health-promoting neighbourhoods in Aotearoa New Zealand.

Our study sought to understand adult decision-makers' views on what was important for actualising children's ideas using co-design, towards creating health-promoting local environments. Ten adult decision-makers, experienced in co-design with children aged 5-13 years in Aotearoa New Zealand, participated in individual interviews. We generated three themes (Empowering children within co-design; Being intentional about children's influence; Curating who is involved) using reflexive thematic analysis. Our themes informed a novel framework of 'impactful co-design' accompanied by a practical checklist for adult decision-makers (practitioners, policy-makers, and researchers). Study findings affirm co-designing local neighbourhoods as an inherently social and technical endeavour, advocate for greater consideration of inclusivity and cultural context, and highlight the need for co-design with children to include safety, empowerment, and evaluation. We position impactful co-design as one useful process to enact children's meaningful participation.