Introduction
movement behaviors
CHILDHOOD OBESITY
Establishing optimal nutrition and movement behaviors (physical activity and sedentary behavior) in early life is critical for achieving health and wellbeing benefits that track into adulthood, including preventing overweight and obesity (Scale-up refers to the expansion of health interventions or innovations tested under research conditions to reach more people and achieve sustained benefits (Behavior change interventions for preventing childhood obesity are complex and contain multiple components. It is vital to have methods for describing intervention components with consistency, transferability, and specificity (Describing intervention components can contribute to developing, enhancing, and understanding effective behavior change interventions. Building on previous work examining BCTs used in early childhood obesity prevention interventions in Australia and New Zealand (The INFANT (INfant Feeding, Active play and NuTrition) program is the first evidence-based early childhood intervention targeting parents and caregivers aiming to improve child nutrition and movement behaviors to be scaled-up in Australia. INFANT was developed with input from child health experts, health professionals and parents and, in 2008, was delivered as a randomized controlled trial (RCT) with 542 families in Victoria, Australia (In 2012, INFANT was delivered as a small-scale translation trial, where uptake was high and provided proof of concept for implementation at scale (The aim of this study is to examine how the intervention components (target behaviors, delivery features and BCTs) of INFANT changed from RCT to scale-up, and to explore factors that influenced these modifications. This will provide important new insights into how scale-up may impact the components of behavioral interventions to then better understand, and potentially mitigate, the frequently observed scale-up penalty.