Scalability and scaling-up strategy of a physical activity policy intervention in Australian childcare centres.

There is an urgent need for scalable interventions to promote physical activity in early childhood. An early childhood education and care (ECEC) physical activity policy intervention with implementation support strategies (Play Active) has been proposed for scale-up in Australia. This study sought to assess the scalability of Play Active and describe the Play Active scaling-up strategy. The Intervention Scalability Assessment Tool was used to assess scalability. The PRACTical planning for Implementation and Scale-up (PRACTIS) guided the scaling-up strategy and involved: (i) characterizing the implementation setting; (ii) identifying existing/new partnerships; (iii) identifying barriers and facilitators to implementation; (iv) addressing barriers through adaptations. The Play Active scalability assessment domains with the highest scores (>2.5/3) were for the problem, intervention, reach and acceptability. Four additional domains scored highly (>2/3): fidelity and adaptation, delivery settings and workforce, implementation infrastructure, and strategic/political context. The lowest scores (<2/3) were the evidence of effectiveness, intervention costs and benefits, and sustainability domains. The PRACTIS guide showed that the implementation setting and existing and new partnerships were appropriate for scaling-up Play Active. The PRACTIS guide also identified key barriers (e.g. staff time) and enablers (e.g. staff professional development) to implementation at scale. Adaptations were identified to address these barriers (e.g. intervention delivery via a customised website). Overall, the scalability assessment revealed gaps in some scalability domains to be addressed through further research and adaptation of Play Active. The proposed scale-up trial evaluation is crucial to support decision-makers to fund, scale and institutionalize Play Active in the real world.